atomic mass (ma)
[ /əˈtɑmɪk mæs/ ]
原子质量
📖 定义
The mass of an atom of a chemical element expressed in atomic mass units. It is approximately equivalent to the number of protons and neutrons in the atom (the mass number) or to the average number allowing for the relative abundances of different isotopes.
average atomic mass
[ /ˈævərɪʤ əˈtɑmɪk mæs/ ]
相对原子质量
📖 定义
The average atomic mass of carbon is 12.011. This is a weighted average based on three forms (isotopes) of carbon with different natural abundances. Carbon 12 has an atomic mass of 12.00 (carbon 12 is a special case because its mass is defined to be exactly 12 atomic mass units) and a natural abundance of 0.9893.
mass units (symbol: u, or Da)
[ /mæs ˈjunɪts ˈsɪmbəl ju ər ˈdiˈeɪ/ ]
原子质量单位
📖 定义
The unified atomic mass unit or Dalton (symbol: u, or Da) is a standard unit of mass that quantifies mass on an atomic or molecular scale (atomic mass). One unified atomic mass unit is approximately the mass of one nucleon (either a single proton or neutron) and is numerically equivalent to 1 g/mol.
proton
[ /ˈproʊˌtɑn/ ]
质子
📖 定义
A stable subatomic particle occurring in all atomic nuclei, with a positive electric charge equal in magnitude to that of an electron, but of opposite sign.
neutron
[ /ˈnuˌtrɑn/ ]
中子
📖 定义
The neutron is a subatomic particle, symbol n or n0, with no net electric charge and a mass slightly larger than that of a proton. Protons and neutrons constitute the nuclei of atoms.
mass number
[ /mæs ˈnəmbər/ ]
质量数
📖 定义
The mass number (A), also called atomic mass number or nucleon number, is the total number of protons and neutrons (together known as nucleons) in an atomic nucleus. It determines the atomic mass of atoms. Because protons and neutrons both are baryons, the mass number A is identical with the baryon number B as of the nucleus as of the whole atom or ion.
isotopic mass
[ /ˌaɪsəˈtɑːpɪk mæs/ ]
同位素质量
📖 定义
The atomic mass (relative isotopic mass) is defined as the mass of a single atom, which can only be one isotope (nuclide) at a time, and is not an abundance-weighted average, as in the case of relative atomic mass/atomic weight.
property
[ /ˈprɑpərti/ ]
性质
📖 定义
A property or characteristic of a substance that is observed during a reaction in which the chemical composition or identity of the substance is changed: Combustibility is an important chemical property to consider when choosing building materials.
composition
[ /ˌkɑmpəˈzɪʃən/ ]
组成
📖 定义
The nature of something's ingredients or constituents; the way in which a whole or mixture is made up.
element
[ /ˈɛləmənt/ ]
元素
📖 定义
Elements are substances that cannot be decomposed into simpler substances. On the molecular level, each element is composed of only one kind of atom.
compound
[ /ˈkɑmpaʊnd/ ]
化合物
📖 定义
Compounds are substances composed of two or more elements; they contain two or more kinds of atoms.
Mixture
[ /ˈmɪksʧər/ ]
混合物
📖 定义
Mixtures are combinations of two or more substances in which each substance retains its chemical identity.
molecule
[ /ˈmɑləˌkjul/ ]
分子
📖 定义
A molecule is an entity composed of two or more atoms with the atoms attached to one another in a specific way.
percent composition
[ /pərˈsɛnt ˌkɑmpəˈzɪʃən/ ]
组成百分比
📖 定义
Percent composition is the term used to describe the percent by mass of each element in a compound. It is typically found using the molar mass values for both the elements in the compound and the compound itself.
empirical formula
[ /ˌɛmˈpɪrɪkəl ˈfɔrmjələ/ ]
经验式
📖 定义
In chemistry, the empirical formula of a chemical compound is the simplest positive integer ratio of atoms present in a compound. A simple example of this concept is that the empirical formula of sulfur monoxide, or SO, would simply be SO, as is the empirical formula of disulfur dioxide, S2O2.
molar ratio
[ /mˈoʊlər ˈreɪʃiˌoʊ/ ]
摩尔比例
📖 定义
Molar ratio is the proportion of one substance to another in a given chemical reaction. It is the ratio of their coefficients in the chemical equation.
molecular formula
[ /məˈlɛkjələr ˈfɔrmjələ/ ]
分子式
📖 定义
Molecular Formula. The molecular formula is an expression of the number and type of atoms that are present in a single molecule of a substance. It represents the actual formula of a molecule. Subscripts after element symbols represent the number of atoms.
whole-number
[ /hˈoʊlənbˌaʊmər/ ]
整数
📖 定义
A number without fractions; an integer.
monoprotic acid
[ /mˌɑːnəprˈɑːtɪk ˈæsəd/ ]
一元酸 [注: 原PDF作单元酸]
📖 定义
A monoprotic acid is an acid that donates only one proton or hydrogen atom per molecule to an aqueous solution. This is in contrast to acids capable of donating more than one proton or hydrogen, which are called polypro tic acids.
Mole
[ /moʊl/ ]
摩尔
📖 定义
Moles are small mammals adapted to a subterranean lifestyle. They have cylindrical bodies; velvety fur; very small, inconspicuous ears and eyes; reduced hind limbs; and short, powerful forelimbs with large paws adapted for digging.
Avogadro’s Number
[ /ˌævəˈɡɑːdroʊ ɛs ˈnəmbər/ ]
阿伏伽德罗常数
📖 定义
In chemistry and physics, the Avogadro constant is the number of constituent particles, usually atoms or molecules, that are contained in the amount of substance given by one mole. Thus, it is the proportionality factor that relates the molar mass of a compound to the mass of a sample.
stoichiometry
[ /ˌstɔɪkiˈɑːmətri/ ]
化学计量学 / 化学计量
📖 定义
Stoichiometry /ˌstɔɪkiˈɒmᵻtri/ is the calculation of relative quantities of reactants and products in chemical reactions. Stoichiometry is founded on the law of conservation of mass where the total mass of the reactants equals the total mass of the products leading to the insight that the relations among quantities of reactants and products typically form a ratio of positive integers.
Molar Mass
[ /mˈoʊlər mæs/ ]
摩尔质量
📖 定义
In chemistry, the molar mass M is a physical property defined as the mass of a given substance (chemical element or chemical compound) divided by the amount of substance. The base SI unit for molar mass is kg/mol.
conversion factors
[ /kənˈvərʒən ˈfæktərz/ ]
转换因子
📖 定义
The easiest way to do stoichiometric calculations involves using conversion factors. A conversion factor is a ratio (or fraction) which represents the relationship between two different units. A conversion factor is ALWAYS equal to 1.
balanced chemical equations
[ /ˈbælənst ˈkɛmɪkəl ɪkˈweɪʒənz/ ]
平衡的化学方程式
📖 定义
A balanced chemical equation is when both the products and the reactants are balanced, or have the same number of atoms on each side of the equation.
dissolve
[ /dɪˈzɑlv/ ]
溶解
📖 定义
In science, dissolve means forming strong bonds between molecules of solute &solvent to form a complete solution which cannot be separated by simple processes like filtration.
density
[ /ˈdɛnsɪti/ ]
密度
📖 定义
The density, or more precisely, the volumetric mass density, of a substance is its mass per unit volume. The symbol most often used for density is ρ (the lower case Greek letter rho), although the Latin letter D can also be used.
Coulomb’s law
[ /ˈkuːlɑːm ɛs lɔ/ ]
库仑定律
📖 定义
Coulomb's law or Coulomb's inverse-square law, is a law of physics that describes force interacting between static electrically charged particles, where ke is Coulomb's constant, q1 and q2 are the signed magnitudes of the charges, the scalar r is the distance between the charges.
ionic solid
[ /ˌaɪˈɑnɪk ˈsɑləd/ ]
离子晶体
📖 定义
Ionic solids are solids composed of oppositely charged ions. They consist of positively charged cations and negatively charged anions .When Ionic Solids are dissolved in water the cations and the anions separate, they become free to move about in the water allowing the solution to conduct electrical current.
lattice energy
[ /ˈlætəs ˈɛnərʤi/ ]
晶格能
📖 定义
Lattice energy, the energy needed to completely separate an ionic solid, such as common table salt, into gaseous ions (also the energy released in the reverse process). Lattice energy is usually measured in kilojoules per mole (1 mole = 6.0221367 * 1023).
ionization energy
[ /ˌaɪənəˈzeɪʃən ˈɛnərʤi/ ]
电离能
📖 定义
The ionization energy (IE) is qualitatively defined as the amount of energy required to remove the most loosely bound electron of an isolated gaseous atom to form a cation, where X is any atom or molecule capable of being ionized, X is that atom or molecule with an electron removed, and e is the removed electron. This is an endothermic process.
electron
[ /ˌɪˈlɛktrɑn/ ]
电子
📖 定义
A stable subatomic particle with a charge of negative electricity, found in all atoms and acting as the primary carrier of electricity in solids.
first ionization energy
[ /fərst ˌaɪənəˈzeɪʃən ˈɛnərʤi/ ]
第一电离能
📖 定义
By definition, the first ionization energy of an element is the energy needed to remove the outermost, or highest energy, electron from a neutral atom in the gas phase.
second ionization energy
[ /ˈsɛkənd ˌaɪənəˈzeɪʃən ˈɛnərʤi/ ]
第二电离能
📖 定义
Second ionization energy is the energy needed to remove a second electron from an atom after one has already been removed. It always takes energy to remove electrons from atoms, although the amount of energy varies greatly. This process is known as ionization, which makes charged ions from neutral atoms.
Aufbau Principle
[ /ˈaʊfbaʊ ˈprɪnsəpəl/ ]
构筑原理
📖 定义
The Aufbau Principle, from the German Aufbauprinzip (building-up principle), also called the Aufbau Rule, states that in the ground state of an atom or ion, electrons fill atomic orbitals of the lowest available energy levels before occupying higher levels.
Pauli Exclusion Principle
[ /ˈpaʊli ɪkˈskluʒən ˈprɪnsəpəl/ ]
泡利不相容原理
📖 定义
The Pauli exclusion principle is the quantum mechanical principle that states that two identical fermions (particles with half-integer spin) cannot occupy the same quantum state simultaneously.
Hund’s Rule
[ /hʊnd ɛs rul/ ]
洪特规则
📖 定义
In atomic physics, Hund's rules refers to a set of rules that German physicist Friedrich Hund formulated around 1927, which are used to determine the term symbol that corresponds to the ground state of a multi-electron atom. The first rule is especially important in chemistry, where it is often referred to as, simply, Hund's Rule.
electron configuration
[ /ˌɪˈlɛktrɑn kənˌfɪgjərˈeɪʃən/ ]
电子排布
📖 定义
In atomic physics and quantum chemistry, the electron configuration is the distribution of electrons of an atom or molecule (or other physical structure) in atomic or molecular orbitals. For example, the electron configuration of the neon atom is 1s² 2s² 2p⁶.
noble gas
[ /ˈnoʊbəl gæs/ ]
惰性气体
📖 定义
The noble gases make a group of chemical elements with similar properties. Under standard conditions, they are all odorless, colorless, monatomic gases with very low chemical reactivity. The six noble gases that occur naturally are helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and the radioactive radon (Rn).
excited state
[ /ɪkˈsaɪtɪd steɪt/ ]
激发态
📖 定义
In quantum mechanics an excited state of a system (such as an atom, molecule or nucleus) is any quantum state of the system that has a higher energy than the ground state (that is, more energy than the absolute minimum).
ground state
[ /graʊnd steɪt/ ]
基态
📖 定义
The ground state of a quantum mechanical system is its lowest-energy state; the energy of the ground state is known as the zero-point energy of the system. An excited state is any state with energy greater than the ground state.
momentum
[ /moʊˈmɛntəm/ ]
动量
📖 定义
The quantity of motion of a moving body, measured as a product of its mass and velocity.
the Heisenberg uncertainty principle
[ /ðə ˈhaɪzənbɜːrɡ ənˈsərtənti ˈprɪnsəpəl/ ]
海森堡测不准原理
📖 定义
In quantum mechanics, the uncertainty principle (also known as Heisenberg's uncertainty principle) is any of a variety of mathematical inequalities asserting a fundamental limit to the precision with which certain pairs of physical properties of a particle, known as complementary variables, such as position x and momentum p, can be known.
Rydberg equation
[ /ˈrɪdbɜːrɡ ɪkˈweɪʒən/ ]
里德堡方程
📖 定义
The Rydberg formula is used in atomic physics to describe the wavelengths of spectral lines of many chemical elements. It was formulated by the Swedish physicist Johannes Rydberg, and presented on 5 November 1888.
orbital
[ /ˈɔrbətəl/ ]
轨道
📖 定义
In chemistry and quantum mechanics, an orbital is a mathematical function that describes the wavelike behavior of an electron, electron pair, or (less commonly) nucleons. An orbital may also be called an atomic orbital or electron orbital.
Periodic Table of the Elements
[ /ˌpɪriˈɑdɪk ˈteɪbəl əv ðə ˈɛləmənts/ ]
元素周期表
📖 定义
The periodic table is a tabular arrangement of the chemical elements, ordered by their atomic number (number of protons), electron configurations, and recurring chemical properties. This ordering shows periodic trends, such as elements with similar behavior in the same column. It also shows four rectangular blocks with some approximately similar chemical properties.
atomic symbols
[ /əˈtɑmɪk ˈsɪmbəlz/ ]
元素符号 [注: 原PDF误作元字符号]
📖 定义
Atomic symbol, sometimes called a chemical symbol, is a one to three letter code for chemical elements.
formula
[ /ˈfɔrmjələ/ ]
方程式
📖 定义
A mathematical relationship or rule expressed in symbols.
ion
[ /aɪən/ ]
离子
📖 定义
An atom or molecule with a net electric charge due to the loss or gain of one or more electrons.
isotope
[ /ˈaɪsətoʊp/ ]
同位素
📖 定义
Isotopes are variants of a particular chemical element which differ in neutron number, although all isotopes of a given element have the same number of protons in each atom. The term isotope is formed from the Greek roots isos and topos, meaning "the same place"; thus, the meaning behind the name is that different isotopes of a single element occupy the same position on the periodic table.
subscript
[ /sˈʌbskrˌɪpt/ ]
下标
📖 定义
(of a letter, figure, or symbol) Written or printed below the line.
atomic number
[ /əˈtɑmɪk ˈnəmbər/ ]
原子序数
📖 定义
In chemistry and physics, the atomic number of a chemical element (also known as its proton number) is the number of protons found in the nucleus of an atom of that element, and therefore identical to the charge number of the nucleus. It is conventionally represented by the symbol Z. The atomic number uniquely identifies a chemical element.
weighted averages of the masses
[ /ˈweɪtɪd ˈævrɪʤɪz əv ðə ˈmæsɪz/ ]
平均质量
📖 定义
To find the AVERAGE ATOMIC MASS of an atom, we take into account all of the isotopes that exist and the percentage of each type. The calculation of the average atomic mass is a WEIGHTED AVERAGE. Average atomic mass = Σ (mass of isotope × relative abundance)
main group
[ /meɪn grup/ ]
主族
📖 定义
In chemistry and atomic physics, the main group is the group of elements whose lightest members are represented by helium, lithium, beryllium, boron, carbon, nitrogen, oxygen, fluorine, and neon as arranged in the periodic table of the elements. The main group includes the elements (except hydrogen) in groups 1 and 2 (s-block), and groups 13 to 18 (p-block).
atomic radius
[ /əˈtɑmɪk ˈreɪdiəs/ ]
原子半径
📖 定义
The atomic radius of a chemical element is a measure of the size of its atoms, usually the mean or typical distance from the center of the nucleus to the boundary of the surrounding cloud of electrons. Since the boundary is not a well-defined physical entity, there are various non-equivalent definitions of atomic radius.
nuclear charge
[ /ˈnukliər ʧɑrʤ/ ]
核电核力
📖 定义
The nuclear charge is the total charge of all the protons in the nucleus. It has the same value as the atomic number.
effective nuclear charge
[ /ˈifɛktɪv ˈnukliər ʧɑrʤ/ ]
有效核电荷数
📖 定义
The effective nuclear charge is the net positive charge experienced by an electron in a multi-electron atom. The term "effective" is used because the shielding effect of negatively charged electrons prevents higher orbital electrons from experiencing the full nuclear charge of the nucleus due to the repelling effect of inner-layer electrons.
electronegativity
[ /ɪˌlɛktroʊˌnɛɡəˈtɪvəti/ ]
电负性
📖 定义
Electronegativity, symbol χ, is a chemical property that describes the tendency of an atom or a functional group to attract electrons (or electron density) towards itself. An atom's electronegativity is affected by both its atomic number and the distance at which its valence electrons reside from the charged nucleus.
affinity
[ /əˈfɪnɪti/ ]
亲和性
📖 定义
In chemical physics and physical chemistry, chemical affinity is the electronic property by which dissimilar chemical species are capable of forming chemical compounds.
non-metal
[ /nɑːnmˈɛtəl/ ]
非金属
📖 定义
In chemistry, a non-metal (or non-metal) is a chemical element that mostly lacks metallic attributes. Physically, non-metals tend to have relatively low melting and boiling points, and densities, are mostly brittle if solid, and are usually poor conductors of heat and electricity; chemically, they tend to have relatively high ionization energy, electron affinity, and electronegativity values, and gain or share electrons when they react with other elements or compounds. Seventeen elements are generally classified as non-metals; most are gases (hydrogen, helium, nitrogen, oxygen, fluorine, neon, chlorine, argon, krypton, xenon and radon); one is a liquid (bromine), and a few are solids (carbon, phosphorus, sulfur, selenium, and iodine). Metalloids such as boron, silicon and germanium are sometimes counted as non-metals.
metal
[ /ˈmɛtəl/ ]
金属
📖 定义
A metal (from Greek μέταλλον métallon, "mine, quarry, metal") is a material that, when freshly prepared, polished, or fractured, has a lustrous appearance, and conducts both electricity and heat relatively well. Metals are typically malleable (they can be hammered into thin sheets) or ductile (can be drawn into wires). A metal may be a pure chemical element such as gold, or an alloy of variable composition such as stainless steel, or an alloy of fixed composition, otherwise known as an intermetallic compound, such as one of the nickel aluminides, Ni3Al, NiAl, or NiAl3. Most elemental metals are denser than other elements; iron, for example, is heavier than carbon, and sulfur.
boiling points
[ /ˈbɔɪlɪŋ pɔɪnts/ ]
沸点
📖 定义
The boiling point of a substance is the temperature at which the vapor pressure of the liquid equals the pressure surrounding the liquid and the liquid changes into a vapor. The boiling point of a liquid varies depending upon the surrounding environmental pressure. A liquid in a partial vacuum has a lower boiling point than when that liquid is at atmospheric pressure.
group
[ /grup/ ]
族
📖 定义
In chemistry, a group is a vertical column in the Periodic Table. Groups may be referred to either by number or by name. For example, Group 1 is also known as the Alkali Metals.
valence electrons
[ /ˈveɪləns ˌɪˈlɛktrɑnz/ ]
价电子
📖 定义
In chemistry, a valence electron is an electron that is associated with an atom, and that can participate in the formation of a chemical bond; in a single covalent bond, both atoms in the bond contribute one valence electron in order to form a shared pair.
third ionization energy
[ /θərd ˌaɪənəˈzeɪʃən ˈɛnərʤi/ ]
第三电离能
📖 定义
The third ionization energy is the energy required to form 3+ cations: M 2+ (g) → M 3+ (g) + e-and so on. Ionization energies are always positive numbers, because energy must be supplied (an endothermic energy change) to separate electrons from atoms.
quantum number
[ /kˈwɑntəm ˈnəmbər/ ]
量子数
📖 定义
Quantum numbers describe values of conserved quantities in the dynamics of a quantum system. In the case of quantum numbers of electrons, they can be defined as "the sets of numerical values which give acceptable solutions to the Schrödinger wave equation for the hydrogen atom".
principal quantum number
[ /ˈprɪnsəpəl kˈwɑntəm ˈnəmbər/ ]
主量子数
📖 定义
In quantum mechanics, the principal quantum number (symbolized n) is one of four quantum numbers which are assigned to each electron in an atom to describe that electron's state. As a discrete variable, the principal quantum number is always an integer. As n increases, the number of electronic shells increases and the electron spends more time farther from the nucleus.
angular momentum quantum number
[ /ˈæŋgjələr moʊˈmɛntəm kˈwɑntəm ˈnəmbər/ ]
角量子数
📖 定义
A quantum number for an atomic orbital that determines its orbital angular momentum and describes the shape of the orbital. Also known as the azimuthal quantum number.
sublevel
[ /sˈʌbləvəl/ ]
亚层
📖 定义
A sublevel is an energy level defined by quantum theory. In chemistry, sublevels refer to energies associated with electrons. In physics, sublevels may also refer to energies associated with the nucleus.
magnetic quantum number
[ /mægˈnɛtɪk kˈwɑntəm ˈnəmbər/ ]
磁量子数
📖 定义
In atomic physics, the magnetic quantum number is the third of a set of quantum numbers (the principal quantum number, the azimuthal quantum number, the magnetic quantum number, and the spin quantum number) which describe the unique quantum state of an electron and is designated by the letter m. The magnetic quantum number denotes the energy levels available within a subshell.
spin quantum number
[ /spɪn kˈwɑntəm ˈnəmbər/ ]
自旋量子数
📖 定义
In atomic physics, the spin quantum number is a quantum number that parameterizes the intrinsic angular momentum (or spin angular momentum, or simply spin) of a given particle.
physical properties
[ /ˈfɪzɪkəl ˈprɑpərtiz/ ]
物理性质
📖 定义
A physical property is any property that is measurable, whose value describes a state of a physical system. The changes in the physical properties of a system can be used to describe its transformations or evolutions between its momentary states. Physical properties are often referred to as observables. They are not modal properties. Quantifiable physical property is called physical quantity.
energy level
[ /ˈɛnərʤi ˈlɛvəl/ ]
能级
📖 定义
A quantum mechanical system or particle that is bound—that is, confined spatially—can only take on certain discrete values of energy. This contrasts with classical particles, which can have any energy. These discrete values are called energy levels.
Democritus
[ /dəmˈɑːkrətəs/ ]
德谟克利特
📖 定义
(c.460–c.370 bc) Greek philosopher. He developed the atomic theory originated by his teacher, Leucippus, which explained natural phenomena in terms of the arrangement and rearrangement of atoms moving in a void.
atom
[ /ˈætəm/ ]
原子
📖 定义
An atom is the smallest constituent unit of ordinary matter that has the properties of a chemical element. Every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. Atoms are extremely small; typical sizes are around 100 picometers. Atoms are small enough that attempting to predict their behavior using classical physics – as if they were billiard balls, for example – gives noticeably incorrect predictions due to quantum effects.
atomic theory
[ /əˈtɑmɪk ˈθɪri/ ]
原子理论
📖 定义
In chemistry and physics, atomic theory is a scientific theory of the nature of matter, which states that matter is composed of discrete units called atoms. It began as a philosophical concept in ancient Greece and entered the scientific mainstream in the early 19th century when discoveries in the field of chemistry showed that matter did indeed behave as if it were made up of atoms.
plum pudding model
[ /pləm ˈpʊdɪŋ ˈmɑdəl/ ]
枣糕模型
📖 定义
The plum pudding model was a model of the atom that incorporated the recently discovered electron, and was proposed by J. J. Thomson in 1904. Thomson had discovered the electron in 1897.
Solar System model
[ /ˈsoʊlər ˈsɪstəm ˈmɑdəl/ ]
原子太阳系模型
📖 定义
An analogy often used in chemistry to describe the atom as “the solar system”, but not everyone agrees on its helpfulness.
chemical reactions
[ /ˈkɛmɪkəl riˈækʃənz/ ]
化学反应
📖 定义
A chemical reaction is a process that leads to the transformation of one set of chemical substances to another. Classically, chemical reactions encompass changes that only involve the positions of electrons in the forming and breaking of chemical bonds between atoms, with no change to the nuclei (no change to the elements present), and can often be described by a chemical equation.
John Dalton
[ /ʤɑn ˈdɔːltən/ ]
约翰·道尔顿
📖 定义
John Dalton FRS (/ˈdɔːltən/; 6 September 1766 – 27 July 1844) was an English chemist, physicist, and meteorologist. He is best known for introducing the atomic theory into chemistry, and for his research into color blindness, sometimes referred to as Daltonism in his honor.
law of multiple proportions
[ /lɔ əv ˈməltəpəl prəˈpɔrʃənz/ ]
倍比定律
📖 定义
Law of multiple proportions, statement that when two elements combine with each other to form more than one compound, the weights of one element that combine with a fixed weight of the other are in a ratio of small whole numbers.
J. J. Thomson
[ /ʤeɪ ʤeɪ ˈtɑmsən/ ]
约瑟夫·汤姆孙
📖 定义
Sir Joseph John Thomson OM PRS (18 December 1856 – 30 August 1940) was an English physicist and Nobel Laureate in Physics, credited with the discovery and identification of the electron; and with the discovery of the first subatomic particle.
Henri Becquerel
[ /ˌɔˈri bˈɛkwˌɛrəl/ ]
法国物理学家贝克勒尔
📖 定义
Antoine Henri Becquerel was a French physicist, Nobel laureate, and the first person to discover evidence of radioactivity. For work in this field he, along with Marie Skłodowska-Curie and Pierre Curie, received the 1903 Nobel Prize in Physics. The SI unit for radioactivity, the becquerel, is named after him.
Marie Curie
[ /mərˈi ˈkjʊri/ ]
居里夫人
📖 定义
Marie Skłodowska Curie (/ˈkjʊəri/;[3] French: [kyʁi]; Polish: [kʲiˈri]; born Maria Salomea Skłodowska;7 November 1867 – 4 July 1934) was a Polish and naturalized-French physicist and chemist who conducted pioneering research on radioactivity. She was the first woman to win a Nobel Prize, the first person and only woman to win twice, the only person to win a Nobel Prize in two different sciences, and was part of the Curie family legacy of five Nobel Prizes. She was also the first woman to become a professor at the University of Paris, and in 1995 became the first woman to be entombed on her own merits in the Panthéon in Paris.
hydrogen spectrum
[ /ˈhaɪdrəʤən ˈspɛktrəm/ ]
氢原子光谱
📖 定义
The emission spectrum of atomic hydrogen is divided into a number of spectral series, with wavelengths given by the Rydberg formula. These observed spectral lines are due to the electron making transitions between two energy levels in the atom. The classification of the series by the Rydberg formula was important in the development of quantum mechanics.
The Wave-Mechanical Model
[ /ðə wˌeɪvəmˈɛkʃənəkəl ˈmɑdəl/ ]
波动力学模型
📖 定义
The wave mechanical model is used to predict the behavior of every electron within an atom. The predictions that are obtained when using the wave mechanical model ensure that the findings are as accurate as possible.
cathode ray
[ /ˈkæˌθoʊd reɪ/ ]
阴极射线 [注: 原PDF误作阴极]
📖 定义
Cathode rays (also called an electron beam or e-beam) are streams of electrons observed in vacuum tubes.
Robert Millikan
[ /ˈrɑbərt ˈmɪləkən/ ]
物理学家密里根
📖 定义
Robert Andrews Millikan (March 22, 1868 – December 19, 1953) was an American experimental physicist honored with the Nobel Prize for Physics in 1923 for the measurement of the elementary electronic charge and for his work on the photoelectric effect. Millikan graduated from Oberlin College in 1891 and obtained his doctorate at Columbia University in 1895. In 1896 he became an assistant at the University of Chicago, where he became a full professor in 1910.
nucleus
[ /ˈnukliəs/ ]
原子核
📖 定义
The positively charged central core of an atom, consisting of protons and neutrons and containing nearly all its mass.
Chadwick Sir James,
[ /ˈʧædwɪk sər ʤeɪmz/ ]
查德威克（姓氏；1891-1974，英国物理学家，中子的发现者，曾获1935 年诺贝尔物理学奖）
📖 定义
Sir James Chadwick, CH, FRS (20 October 1891 – 24 July 1974) was a British physicist who was awarded the 1935 Nobel Prize in Physics for his discovery of the neutron in 1932. In 1941, he wrote the final draft of the MAUD Report, which inspired the U.S. government to begin serious atomic bomb research efforts. He was the head of the British team that worked on the Manhattan Project during the Second World War. He was knighted in Britain in 1945 for his achievements in physics.
Bohr Model of the Atom
[ /bɔr ˈmɑdəl əv ðə ˈætəm/ ]
波尔原子模型
📖 定义
In atomic physics, the Rutherford–Bohr model or Bohr model, introduced by Niels Bohr in 1913, depicts the atom as a small, positively charged nucleus surrounded by electrons that travel in circular orbits around the nucleus—similar in structure to the solar system, but with attraction provided by electrostatic forces rather than gravity.
subatomic particle
[ /ˌsəbəˈtɑmɪk ˈpɑrtɪkəl/ ]
亚原子粒子
📖 定义
In the physical sciences, subatomic particles are particles much smaller than atoms. There are two types of subatomic particles: elementary particles, which according to current theories are not made of other particles; and composite particles. Particle physics and nuclear physics study these particles and how they interact.
mass spectrometer
[ /mæs spɛkˈtrɑmətər/ ]
质谱
📖 定义
Mass spectrometry (MS) is an analytical technique that ionizes chemical species and sorts the ions based on their mass-to-charge ratio.
negatively charged
[ /ˈnɛgətɪvli ʧɑrʤd/ ]
负电
📖 定义
A negatively charged atom is called an anion. An anion forms when an atom gains electrons from another atom. Atoms are generally neutral, but they take on a charge when they gain or lose electrons.
magnet
[ /ˈmægnət/ ]
磁石
📖 定义
A magnet is a material or object that produces a magnetic field. This magnetic field is invisible but is responsible for the most notable property of a magnet: a force that pulls on other ferromagnetic materials, such as iron, and attracts or repels other magnets.
relative isotopic abundances
[ /ˈrɛlətɪv ˌaɪsəˈtɑːpɪk əbˈʌndənsɪz/ ]
同位素丰度
📖 定义
The relative atomic mass is the weighted average of the isotopic masses. Example: Chlorine has two isotopes 35Cl and 37Cl, with relative abundance of 75% and 25% respectively. This means that in any naturally occurring sample of chlorine 75% of the atoms are Cl-35 atoms and 25% of the atoms are chlorine-37 atoms.
photon
[ /ˈfoʊˌtɑn/ ]
光子
📖 定义
A photon is an elementary particle, the quantum of all forms of electromagnetic radiation, including light. It is the force carrier for the electromagnetic force, even when static via virtual photons. The photon has zero rest mass and as a result, the interactions of this force with matter at long distance are observable at the microscopic and at the macroscopic level.
frequency
[ /ˈfrikwənsi/ ]
频率
📖 定义
Frequency is the number of times a point on a wave passes a fixed reference point in one second. The SI unit for frequency is the Hertz (Hz). Also Known As: cycles per second. Article. Chemistry. These Are the Base Units of the Metric System The metric system or SI is based on seven base units.
electromagnetic
[ /ˌɪˌlɛktroʊmægˈnɛtɪk/ ]
电磁的 adj.
📖 定义
Of or exhibiting electromagnetism.
Planck’s equation
[ /plæŋk ɛs ɪkˈweɪʒən/ ]
普朗克方程
📖 定义
Planck's law describes the spectral density of electromagnetic radiation emitted by a black body in thermal equilibrium at a given temperature T. The law is named after Max Planck, who proposed it in 1900. It is a pioneering result of modern physics and quantum theory.
ionization
[ /ˌaɪənəˈzeɪʃən/ ]
电离化
📖 定义
Ionization or ionisation, is the process by which an atom or a molecule acquires a negative or positive charge by gaining or losing electrons to form ions, often in conjunction with other chemical changes.
wave-particle duality
[ /weɪv ˈpɑːrtɪkəl duˈæləti/ ]
波粒二象性 [注: 原PDF误作波粒二线性]
📖 定义
Wave–particle duality is the concept that every elementary particle or quantic entity may be partly described in terms not only of particles, but also of waves. It expresses the inability of the classical concepts "particle" or "wave" to fully describe the behavior of quantum-scale objects.
diffraction
[ /dɪˈfrækʃən/ ]
衍射
📖 定义
The process by which a beam of light or other system of waves is spread out as a result of passing through a narrow aperture or across an edge, typically accompanied by interference between the wave forms produced.
absorbance
[ /ˈæbsərbˌæns/ ]
吸收率
📖 定义
In chemistry, absorbance or decadic absorbance is the common logarithm of the ratio of incident to transmitted radiant power through a material, and spectral absorbance or spectral decadic absorbance is the common logarithm of the ratio of incident to transmitted spectral radiant power through a material.
solute
[ /sˈoʊluːt/ ]
溶质
📖 定义
In chemistry, a solution is a special type of homogeneous mixture composed of two or more substances. The term aqueous solution is when one of the solvents is water. In such a mixture, a solute is a substance dissolved in another substance, known as a solvent. The mixing process of a solution happens at a scale where the effects of chemical polarity are involved, resulting in interactions that are specific to solvation.
solution
[ /səˈluʃən/ ]
溶液
📖 定义
In chemistry, a solution is a special type of homogeneous mixture composed of two or more substances. The term aqueous solution is when one of the solvents is water.
Beer’s law
[ /bɪr ɛs lɔ/ ]
比尔定律（比尔-朗伯定律）[注: 原PDF误作波尔定律]
📖 定义
Beer’s law, also called Lambert-Beer law or Beer-Lambert law, states that the concentration of an analyte is directly proportional to the amount of light absorbed.
ultraviolet
[ /ˌəltrəˈvaɪəlɪt/ ]
紫外的
📖 定义
Ultraviolet is electromagnetic radiation with a wavelength from 10 nm to 400 nm, shorter than that of visible light but longer than X-rays. UV radiation is present in sunlight constituting about 10% of the total light output of the Sun. It is also produced by electric arcs and specialized lights, such as mercury-vapor lamps, tanning lamps, and black lights.
X-ray
[ /ˈɛksˌreɪ/ ]
X 射线
📖 定义
X-radiation (composed of X-rays) is a form of electromagnetic radiation. Most X-rays have a wavelength ranging from 0.01 to 10 nanometers, corresponding to frequencies in the range 30 petahertz to 30 exahertz and energies in the range 100 eV to 100 keV. X-ray wavelengths are shorter than those of UV rays and typically longer than those of gamma rays.
infrared
[ /ˌɪnfrərˈɛd/ ]
红外的
📖 定义
(Of electromagnetic radiation) Having a wavelength just greater than that of the red end of the visible light spectrum but less than that of microwaves. Infrared radiation has a wavelength from about 800 nm to 1 mm, and is emitted particularly by heated objects.
reactant
[ /riːˈæktənt/ ]
反应物
📖 定义
A substance that takes part in and undergoes change during a reaction.
product
[ /ˈprɑdəkt/ ]
产物
📖 定义
Product (chemistry) Products are the species formed from chemical reactions. During a chemical reaction reactants are transformed into products after passing through a high energy transition state.
sodium hydroxide
[ /ˈsoʊdiəm haɪˈdrɑksaɪd/ ]
氢氧化钠
📖 定义
Sodium hydroxide, also known as lye and caustic soda, is an inorganic compound with the formula NaOH. It is a white solid ionic compound consisting of sodium cations Na⁺ and hydroxide anions OH⁻.
molar ratio
[ /mˈoʊlər ˈreɪʃiˌoʊ/ ]
摩尔比例
📖 定义
Molar ratio is the proportion of one substance to another in a given chemical reaction. It is the ratio of their coefficients in the chemical equation. For example, in the synthesis of water, the mole ratio of Hydrogen (H2) to Oxygen (O2) is 1:2.
Law of Conservation of Mass
[ /lɔ əv ˌkɑnsərˈveɪʃən əv mæs/ ]
质量守恒定律
📖 定义
The law of conservation of mass or principle of mass conservation states that for any system closed to all transfers of matter and energy, the mass of the system must remain constant over time, as system mass cannot change quantity if it is not added or removed. Hence, the quantity of mass is "conserved" over time.
coefficient
[ /ˌkoʊəˈfɪʃənt/ ]
系数
📖 定义
Coefficients are the numbers placed before the reactants in a chemical equation so that the number of atoms in the products on the right side of the equation are equal to the number of atoms in the reactants on the left side.
gravimetric analysis
[ /ˌgrævəˈmɛtrɪk æˈnælɪsɪs/ ]
重量分析
📖 定义
Gravimetric analysis describes a set of methods in analytical chemistry for the quantitative determination of an analyte based on the mass of a solid. For instance, the measurement of solids suspended in a water sample: A known volume of water is filtered, and the collected solids are weighed.
sample
[ /ˈsæmpəl/ ]
样本
📖 定义
A small part or quantity intended to show what the whole is like.
hydrate
[ /ˈhaɪˌdreɪt/ ]
水合物
📖 定义
In chemistry, a hydrate is a substance that contains water or its constituent elements. The chemical state of the water varies widely between different classes of hydrates, some of which were so labelled before their chemical structure was understood.
anion
[ /ˈænaɪən/ ]
阴离子
📖 定义
A negatively charged ion.
ammonia
[ /əˈmoʊnjə/ ]
氨
📖 定义
Ammonia is a compound of nitrogen and hydrogen with the formula NH3. The simplest pnictogen hydride, ammonia, is a colorless gas with a characteristic pungent smell. It is a common nitrogenous waste, particularly among aquatic organisms, and it contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to food and fertilizers.
titration
[ /taɪˈtreɪʃən/ ]
滴定
📖 定义
Titration, also known as titrimetry, is a common laboratory method of quantitative chemical analysis that is used to determine the concentration of an identified analyte. Since volume measurements play a key role in titration, it is also known as volumetric analysis. A reagent, called the titrant or titrator, is prepared as a standard solution. A known concentration and volume of titrant reacts with a solution of analyte or titrand to determine concentration. The volume of titrant reacted is called titration volume.
crystal
[ /ˈkrɪstəl/ ]
晶体
📖 定义
A crystal or crystalline solid is a solid material whose constituents, such as atoms, molecules or ions, are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions. In addition, macroscopic single crystals are usually identifiable by their geometrical shape, consisting of flat faces with specific, characteristic orientations.
equivalent
[ /ɪkˈwɪvələnt/ ]
等量 adj.
📖 定义
Equal in value, amount, function, and meaning.
spectrophotometry
[ /spˌɛkstˌɑːrθətˈɑːmɪtiː/ ]
分光光度法
📖 定义
In chemistry, spectrophotometry is the quantitative measurement of the reflection or transmission properties of a material as a function of wavelength. It is more specific than the general term electromagnetic spectroscopy in that spectrophotometry deals with visible light, near-ultraviolet, and near-infrared, but does not cover time-resolved spectroscopic techniques.
electrochemical series
[ /ˌəˌlɛktroʊˈkɛmɪkəl ˈsɪriz/ ]
元素电化序
📖 定义
Electrochemical series is a series of chemical elements arranged in order of their standard electrode potentials.
pH indicator
[ /ˈpiˈeɪʧ ˈɪndəˌkeɪtər/ ]
酸碱指示剂
📖 定义
A pH indicator is a halochromic chemical compound added in small amounts to a solution so the pH (acidity or basicity) of the solution can be determined visually. Hence, a pH indicator is a chemical detector for hydronium ions (H 3 O +) or hydrogen ions (H +) in the Arrhenius model.
common-ion effect
[ /kˈɑːmənjən ˈifɛkt/ ]
同离子效应
📖 定义
The common ion effect is responsible for the reduction in the solubility of an ionic precipitate when a soluble compound containing one of the ions of the precipitate is added to the solution in equilibrium with the precipitate.
burette
[ /bjʊˈrɛt/ ]
滴定管
📖 定义
A burette (also burette) is a device used in analytical chemistry for the dispensing of variable, measured amounts of a chemical solution. A volumetric burette delivers measured volumes of liquid. Piston burettes are similar to syringes, but with precision bore and plunger. Piston burettes may be manually operated or may be motorized. A weight burette delivers measured weights of liquid.
buffering effect
[ /ˈbəfərɪŋ ˈifɛkt/ ]
缓冲效果
📖 定义
A buffering effect is a process in which a psychosocial resource reduces the impact of life stress on psycho-logical well-being. Having such a resource contributes to adjustment because persons are less affected by negative life events.
neutral
[ /ˈnutrəl/ ]
中性的 adj.
📖 定义
A neutral pH level is a value of seven on the pH scale. This number lies at the center of the scale and is the value that is associated with pure water. A pH level below or above seven indicates that the liquid is either an acid or a base.
conjugate
[ /ˌkɑnʤəˈgeɪt/ ]
共轭
📖 定义
In chemistry, a conjugated system is a system of connected p-orbitals with delocalized electrons in molecules which are conventionally represented as having alternating single and multiple bonds, which in general may lower the overall energy of the molecule and increase stability.
limiting reagent
[ /ˈlɪmətɪŋ ˈriʤənt/ ]
限量反应物
📖 定义
The limiting reagent (or limiting reactant) in a chemical reaction is the substance that is totally consumed when the chemical reaction is complete. The amount of product formed is limited by this reagent, since the reaction cannot continue without it.
polyprotic acid
[ /pˌɑːlɪprˈoʊtɪk ˈæsəd/ ]
多元酸
📖 定义
A polyprotic acid is an acid which contains more than one ionizable hydrogen (H+) per acid molecule. The acid ionizes one step at a time in an aqueous solution, with a separate ionization constant for each step. The initial dissociation is the primary source of H+, so it is the main factor in determining the pH of the solution.
vacuum
[ /ˈvækjum/ ]
真空
📖 定义
Vacuum is a volume that encloses little or no matter. A partial vacuum is a vacuum with low amounts of matter enclosed. A total or absolute vacuum has no matter enclosed.
filtration
[ /fɪlˈtreɪʃən/ ]
过滤
📖 定义
Filtration is any of various mechanical, physical or biological operations that separate solids from fluids by adding a medium through which only the fluid can pass. The fluid that passes through is called the filtrate. In physical filters oversize solids in the fluid are retained and in biological filters particulates are trapped and ingested and metabolites are retained and removed.
bond
[ /bɑnd/ ]
键
📖 定义
A chemical bond is any of several forces or mechanisms, especially the ionic bond, covalent bond, and metallic bond, by which atoms or ions are bound in a molecule or crystal. There are two types of chemical bonds mainly, these are the ionic and covalent bonds.
melt
[ /mɛlt/ ]
熔化 v.
📖 定义
In physics and chemistry, melting is the process of converting a solid substance to its liquid form, typically by heating the substance to a temperature called its melting point.
amorphous
[ /əˈmɔrfəs/ ]
无定型的 adj.
📖 定义
In physics and chemistry, amorphous is a term used to describe a solid which does not exhibit crystalline structure. While there may be local ordering of the atoms or molecules in an amorphous solid, no long-term ordering is present.
network
[ /ˈnɛtˌwərk/ ]
网络的
📖 定义
A network solid or covalent network solid is a chemical compound (or element) in which the atoms are bonded by covalent bonds in a continuous network extending throughout the material. In a network solid there are no individual molecules, and the entire crystal or amorphous solid may be considered a macromolecule.
polymer
[ /ˈpɑləmər/ ]
聚合物
📖 定义
A polymer is a large molecule, or macromolecule, composed of many repeated subunits. Due to their broad range of properties, both synthetic and natural polymers play essential and ubiquitous roles in everyday life. Polymers range from familiar synthetic plastics such as polystyrene to natural biopolymers such as DNA and proteins that are fundamental to biological structure and function.
surface tension
[ /ˈsərfəs ˈtɛnʃən/ ]
表面张力
📖 定义
Surface tension is the elastic tendency of a fluid surface which makes it acquire the least surface area possible. Surface tension allows insects (e.g. water striders), usually denser than water, to float and stride on a water surface.
intermolecular
[ /ˌɪntərməˈlɛkjələr/ ]
分子之间的 adj.
📖 定义
Existing or taking place between molecules.
viscosity
[ /vɪˈskɑsəti/ ]
粘度
📖 定义
The viscosity of a fluid is a measure of its resistance to gradual deformation by shear stress or tensile stress. For liquids, it corresponds to the informal concept of "thickness". For example, honey has a much higher viscosity than water.
phase
[ /feɪz/ ]
相
📖 定义
A distinct and homogeneous form of matter (i.e. a particular solid, liquid, or gas) separated by its surface from other forms.
a heating curve
[ /ə ˈhitɪŋ kərv/ ]
加热曲线
📖 定义
A heating curve shows the relationship of the temperature and heat input of a system as that system is heated over time.
vapor
[ /ˈveɪpər/ ]
蒸汽
📖 定义
In physics a vapor or vapour is a substance in the gas phase at a temperature lower than its critical temperature, which means that the vapor can be condensed to a liquid by increasing the pressure on it without reducing the temperature. A vapor is different from an aerosol. An aerosol is a suspension of tiny particles of liquid, solid, or both within a gas.
metastable state
[ /mˈɛtəstəbəl steɪt/ ]
亚稳定状态
📖 定义
Metastability denotes the phenomenon when a system spends an extended time in a configuration other than the system's state of least energy. During a metastable state of finite lifetime all state-describing parameters reach and hold stationary values.
macroscopic
[ /mˌærkoʊskˈɑːpɪk/ ]
宏观的 adj.
📖 定义
Visible to the naked eye; not microscopic.
Kinetic Molecular Theory
[ /kɪˈnɛtɪk məˈlɛkjələr ˈθɪri/ ]
分子动能论
📖 定义
The kinetic molecular theory is a collection of several rules that describe the behavior of gases. The nature of gas molecules was examined by scientists, such as Robert Boyle and Jacques Charles, who outlined their observations in several laws that eventually became the Kinetic Molecular Theory.
random
[ /ˈrændəm/ ]
随机的 adj.
📖 定义
Proceeding, made, or occurring without definite aim, reason, or pattern.
pressure
[ /ˈprɛʃər/ ]
压强
📖 定义
Continuous physical force exerted on or against an object by something in contact with it.
proportional
[ /prəˈpɔrʃənəl/ ]
按照比例的 adj.
📖 定义
Corresponding in size or amount to something else.
elastic collision
[ /ɪˈlæstɪk kəˈlɪʒən/ ]
弹性碰撞
📖 定义
Elastic Collision is the collision in which colliding objects rebound without lasting deformation or heat generation. Inelastic collision is a collision in which the colliding objects become distorted and generate heat during collision and possibly stick together.
ideal gas
[ /aɪˈdil gæs/ ]
理想气体
📖 定义
An ideal gas is a theoretical gas composed of many randomly moving point particles that do not interact except when they collide elastically. The ideal gas concept is useful because it obeys the ideal gas law, a simplified equation of state, and is amenable to analysis under statistical mechanics. One mole of an ideal gas has a volume of 22.7 L at STP as defined by IUPAC.
non-polar
[ /nˈɑːnpˌɔːlər/ ]
非极性
📖 定义
A non-polar solvent is one with molecules that have roughly the same electrical charge on all sides; in other words, it has low static permittivity. Non-polar solvents are typically hydrocarbons, such as pentane and hexane. Each atom on the periodic table has an electronegativity value that describes its ability to bond to other atoms.
polar
[ /ˈpoʊlər/ ]
极性
📖 定义
Polar in chemistry, also known as a polar covalent bond, happens when 2 or more non-metals create a bond. Polar bonds are usually liquids or solids and are soluble. For example, water (H2O) is polar covalent. It is made up of Hydrogen and Oxygen, with hydrogen having a partial positive and oxygen with a partial negative.
gas law
[ /gæs lɔ/ ]
气体定理
📖 定义
Laws that relate the pressure, volume, and temperature of a gas.
Boyle’s law
[ /bɔɪl ɛs lɔ/ ]
波义尔定律
📖 定义
Boyle's law (sometimes referred to as the Boyle–Mariotte law, or Mariotte's law) is an experimental gas law that describes how the pressure of a gas tends to increase as the volume of a gas decreases.
Charles’s law
[ /ˈʧɑrəlz ɛs lɔ/ ]
查理定理
📖 定义
Charles' law (also known as the law of volumes) is an experimental gas law that describes how gases tend to expand when heated.
Gay-Lussac’s Law
[ /ɡˈeɪləskə ɛs lɔ/ ]
盖-吕萨克 原理
📖 定义
Gay-Lussac’s law is a gas law that states that the pressure of a given mass of gas varies directly with the absolute temperature of the gas when the volume is kept constant.
Combined Gas Law
[ /kəmˈbaɪnd gæs lɔ/ ]
气体定律
📖 定义
The combined gas law combines the three gas laws: Boyle's Law, Charles' Law, and Gay-Lussac's Law. It states that the ratio of the product of pressure and volume and the absolute temperature of a gas is equal to a constant. When Avogadro's law is added to the combined gas law, the ideal gas law results. Unlike the named gas laws, the combined gas law doesn't have an official discoverer. It is simply a combination of the other gas laws that works when everything except temperature, pressure, and volume are held constant.
Avogadro’s Law
[ /ˌævəˈɡɑːdroʊ ɛs lɔ/ ]
阿伏加德罗定律 [注: 原PDF误作阿伏伽德罗常数]
📖 定义
A modern statement of Avogadro's law is: Avogadro's law states that, "equal volumes of all gases, at the same temperature and pressure, have the same number of molecules". For a given mass of an ideal gas, the volume and amount (moles) of the gas are directly proportional if the temperature and pressure are constant.
Ideal Gas Equation
[ /aɪˈdil gæs ɪkˈweɪʒən/ ]
理想气体方程
📖 定义
The ideal gas law is the equation of state of a hypothetical ideal gas. It is a good approximation to the behavior of many gases under many conditions, although it has several limitations.
ideal gas constant
[ /aɪˈdil gæs ˈkɑnstənt/ ]
理想气体常数
📖 定义
The ideal gas constant is also known as the universal gas constant or the molar gas constant or simply the gas constant, denoted as R. The dimension of the gas constant is expressed in energy per unit mole per unit temperature. The value of the gas constant in SI unit is 8.314 J mol−1 K−1. The gas constant has the same unit as of entropy and molar heat capacity.
Kelvin temperature
[ /ˈkɛlvɪn ˈtɛmpərəʧər/ ]
开尔文温度
📖 定义
The kelvin is a unit of measure for temperature based upon an absolute scale. It is one of the seven base units in the International System of Units (SI) and is assigned the unit symbol K. The Kelvin scale is an absolute, thermodynamic temperature scale using as its null point absolute zero, the temperature at which all thermal motion ceases in the classical description of thermodynamics.
Dalton’s Law of Partial Pressures
[ /ˈdɔːltən ɛs lɔ əv ˈpɑrʃəl ˈprɛʃərz/ ]
道尔顿分压定律
📖 定义
In chemistry and physics, Dalton's law (also called Dalton's law of partial pressures) states that in a mixture of non-reacting gases, the total pressure exerted is equal to the sum of the partial pressures of the individual gases.
Non-Ideal Gases
[ /nˈɑːndˈaɪlə ˈgæsɪz/ ]
非理想气体
📖 定义
An ideal gas is a theoretical idea – a gas in which there are no attractive forces between the molecules, and in which the molecules take up no space. But both of these assumptions are incorrect in the real world. All gases in the real world have molecules with diameters and which interact with each other, so there's always a bit of error involved in using any form of the Ideal Gas Law.
van der Waals equation
[ /væn dər wˈɔːlz ɪkˈweɪʒən/ ]
范德华方程
📖 定义
The van der Waals equation (or van der Waals equation of state) is an equation relating the density of gases and liquids (fluids) to the pressure (p), volume (V), and temperature (T) conditions (i.e., it is a thermodynamic equation of state).
carbon monoxide
[ /ˈkɑrbən məˈnɑksaɪd/ ]
一氧化碳
📖 定义
Carbon monoxide (CO) is a colorless, odorless, and tasteless gas that is slightly less dense than air.
effuse
[ /ɪfjˈuːz/ ]
泻流 v. [注: 区分于扩散 diffuse]
📖 定义
Give off (a liquid, light, smell, or quality).
graduated cylinder
[ /ˈgræʤəˌweɪtɪd ˈsɪlɪndər/ ]
量筒
📖 定义
A graduated cylinder, measuring cylinder or mixing cylinder is a common piece of laboratory equipment used to measure the volume of a liquid. It has a narrow cylindrical shape. Each marked line on the graduated cylinder represents the amount of liquid that has been measured.
absolute temperature
[ /ˈæbsəˌlut ˈtɛmpərəʧər/ ]
绝对温度
📖 定义
A temperature measured from absolute zero in kelvins.
Graham’s law of effusion
[ /græm ɛs lɔ əv ɪfjˈuːʒən/ ]
格拉汉姆气体扩散定律
📖 定义
Graham's law of effusion (also called Graham's law of diffusion) was formulated by Scottish physical chemist Thomas Graham in 1848. Graham found experimentally that the rate of effusion of a gas is inversely proportional to the square root of the mass of its particles.
molar mass
[ /mˈoʊlər mæs/ ]
摩尔质量
📖 定义
In chemistry, the molar mass M is a physical property defined as the mass of a given substance (chemical element or chemical compound) divided by its amount of substance. The base SI unit for molar mass is kg/mol. However, for historical reasons, molar masses are almost always expressed in g/mol.
homogeneous
[ /ˌhoʊməˈʤiniəs/ ]
同质的 adj.
📖 定义
A Homogeneous mixture is a solid, liquid or gaseous mixture that has the same proportions of its components throughout a given sample.
colloid
[ /ˈkɑlɔɪd/ ]
胶体
📖 定义
A homogeneous noncrystalline substance consisting of large molecules or ultramicroscopic particles of one substance dispersed through a second substance. Colloids include gels, sols, and emulsions; the particles do not settle, and cannot be separated out by ordinary filtering or centrifuging like those in a suspension.
heterogeneous
[ /ˌhɛtərəˈʤinjəs/ ]
异质的 adj.
📖 定义
In chemistry, a heterogeneous mixture consists of either or both of a) multiple states of matter or b) hydrophilic and hydrophobic substances in one mixture; an example of the latter would be a mixture of water, octane, and silicone grease.
micrometer
[ /maɪˈkrɑmətər/ ]
千分尺
📖 定义
A micrometer, sometimes known as a micrometer screw gauge, is a device incorporating a calibrated screw widely used for precise measurement of components in mechanical engineering and machining as well as most mechanical trades, along with other metrological instruments such as dial, vernier, and digital calipers.
chromatography
[ /kroʊməˈtɑgrəfi/ ]
层析
📖 定义
Chromatography is the collective term for a set of laboratory techniques for the separation of mixtures. The mixture is dissolved in a fluid called the mobile phase, which carries it through a structure holding another material called the stationary phase. The various constituents of the mixture travel at different speeds, causing them to separate.
intermolecular force
[ /ˌɪntərməˈlɛkjələr fɔrs/ ]
分子间作用力
📖 定义
Intermolecular forces are the forces which mediate interaction between molecules, including forces of attraction or repulsion which act between molecules and other types of neighboring particles, e.g., atoms or ions. Intermolecular forces are weak relative to intramolecular forces – the forces which hold a molecule together. For example, the covalent bond, involving sharing electron pairs between atoms, is much stronger than the forces present between neighboring molecules.
component
[ /kəmˈpoʊnənt/ ]
组成部分
📖 定义
A part or element of a larger whole.
distillation
[ /ˌdɪstəˈleɪʃən/ ]
蒸馏
📖 定义
Distillation is a process of separating the component substances from a liquid mixture by selective evaporation and condensation. Distillation may result in essentially complete separation (nearly pure components), or it may be a partial separation that increases the concentration of selected components of the mixture.
condenser
[ /kənˈdɛnsər/ ]
冷凝器
📖 定义
An apparatus or container for condensing vapor.
permanent dipole
[ /ˈpərmɑˌnɛnt ˈdaɪˌpoʊl/ ]
永久偶极矩
📖 定义
A permanent dipole is created in a molecule when there is an electronegative atom, such as oxygen, nitrogen or a halogen. The permanent dipole consists of regions of partial positive charge and regions of partial negative charge within the same molecule.
hydrogen bonding
[ /ˈhaɪdrəʤən ˈbɑndɪŋ/ ]
氢键
📖 定义
A hydrogen bond is the electrostatic attraction between polar groups that occurs when a hydrogen (H) atom bound to a highly electronegative atom such as nitrogen (N), oxygen (O) or fluorine (F) experiences attraction to some other nearby highly electronegative atom.
melting point
[ /ˈmɛltɪŋ pɔɪnt/ ]
熔点
📖 定义
Melting point, temperature at which the solid and liquid forms of a pure substance can exist in equilibrium. As heat is applied to a solid, its temperature will increase until the melting point is reached. More heat then will convert the solid into a liquid with no temperature change.
sublimation
[ /sˌʌblɪmˈeɪʃən/ ]
升华
📖 定义
Sublimation is the transition of a substance directly from the solid to the gas phase, without passing through the intermediate liquid phase. Sublimation is an endothermic process that occurs at temperatures and pressures below a substance's triple point in its phase diagram, which corresponds to the lowest pressure at which the substance can exist as a liquid. The reverse process of sublimation is deposition or desublimation, in which a substance passes directly from a gas to a solid phase.
dipole
[ /ˈdaɪˌpoʊl/ ]
偶极
📖 定义
A dipole is a separation of electrical charges. In chemistry, a dipole refers to the separation of charges within a molecule between two covalently bonded atoms.
London dispersion force
[ /ˈləndən dɪˈspərʒən fɔrs/ ]
伦敦色散力
📖 定义
London dispersion forces (LDF, also known as dispersion forces, London forces, instantaneous dipole–induced dipole forces, or loosely van der Waals forces) are a type of force acting between atoms and molecules. They are part of the van der Waals forces. The LDF is named after the German-American physicist Fritz London.
temporary dipole
[ /ˈtɛmpərˌɛri ˈdaɪˌpoʊl/ ]
瞬时偶极
📖 定义
Temporary dipoles are when the electron clouds' density around a nucleus shifts in density, forming temporary dipoles. This is to say that the concentration of electrons are more concentrated in one part of a molecule than anywhere else.
straight-chain
[ /strˈeɪtʃˌeɪn/ ]
直链的
📖 定义
A chain of atoms in a molecule, usually carbon atoms, that is neither branched nor formed into a ring.
electronegative
[ /ɪlˌɛktroʊˈæntɪɡət/ ]
负电性的 adj。
📖 定义
(of an element) Tending to acquire electrons and form negative ions in chemical reactions.
three-dimensional
[ /θˌrizdɪˈmɛnʃənəl/ ]
3D 立体的
📖 定义
Having or appearing to have length, breadth, and depth.
capillary action
[ /ˈkæpəˌlɛri ˈækʃən/ ]
毛细作用
📖 定义
Capillary action (sometimes capillarity, capillary motion, or wicking) is the ability of a liquid to flow in narrow spaces without the assistance of, or even in opposition to, external forces like gravity.
miscible
[ /ˈmɪsəbəl/ ]
互溶的 adj.
📖 定义
(of liquids) forming a homogeneous mixture when added together.
soluble
[ /ˈsɑljəbəl/ ]
溶解的 adj.
📖 定义
(of a substance) Able to be dissolved, especially in water.
deviations
[ /diviˈeɪʃənz/ ]
偏差
📖 定义
The amount by which a single measurement differs from a fixed value such as the mean.
hydrophobic
[ /ˌhaɪdrəˈfoʊbɪk/ ]
疏水的 adj.
📖 定义
In chemistry, hydrophobicity is the physical property of a molecule (known as a hydrophobe) that is seemingly repelled from a mass of water.(Strictly speaking, there is no repulsive force involved; it is an absence of attraction.) In contrast, hydrophiles are attracted to water.
hydrophilic
[ /ˌhaɪdrəˈfɪlɪk/ ]
亲水的 adj.
📖 定义
Tending to dissolve in, mix with, or be wetted by water: a hydrophilic colloid. The opposite of hydrophobic.
catalyze
[ /ˈkætəˌlaɪz/ ]
催化 v.
📖 定义
Cause or accelerate (a reaction) by acting as a catalyst.
Enzyme
[ /ˈɛnˌzaɪm/ ]
酶
📖 定义
Enzymes /ˈɛnzaɪmz/ are macromolecular biological catalysts. Enzymes accelerate chemical reactions. The molecules upon which enzymes may act are called substrates and the enzyme converts the substrates into different molecules known as products. Almost all metabolic processes in the cell need enzyme catalysis in order to occur at rates fast enough to sustain life.
covalent bonding
[ /koʊˈveɪlənt ˈbɑndɪŋ/ ]
共价键
📖 定义
Covalent bond, in chemistry, the interatomic linkage that results from the sharing of an electron pair between two atoms. The binding arises from the electrostatic attraction of their nuclei for the same electrons.
polyatomic
[ /pˌɑːliːətˈɑːkəm/ ]
多原子的
📖 定义
A polyatomic ion is an ion consisting of multiple atoms associated together by covalent bonds which can be considered as acting as a single unit in the context of acid/base chemistry or in the formation of salts.
polarity
[ /poʊˈlɛrəti/ ]
极性
📖 定义
In chemistry, polarity is a separation of electric charge leading to a molecule or its chemical groups having an electric dipole or multipole moment. Polar molecules must contain polar bonds due to a difference in electronegativity between the bonded atoms.
electron pair
[ /ˌɪˈlɛktrɑn pɛr/ ]
电子对
📖 定义
In chemistry, an electron pair or a Lewis pair consists of two electrons that occupy the same molecular orbital but have opposite spins. The electron pair concept was introduced in a 1916 paper of Gilbert N. Lewis.
oxidation number
[ /ˌɑksəˈdeɪʃən ˈnəmbər/ ]
氧化数
📖 定义
Oxidation number, also called Oxidation State, the total number of electrons that an atom either gains or loses in order to form a chemical bond with another atom.
bond strength
[ /bɑnd strɛŋθ/ ]
键强度
📖 定义
In chemistry, bond energy (E) or bond enthalpy (H) is the measure of bond strength in a chemical bond. IUPAC defines bond energy as the average value of the gas-phase bond dissociation energies (usually at a temperature of 298 K) for all bonds of the same type within the same chemical species.
bond length
[ /bɑnd lɛŋθ/ ]
键长
📖 定义
In molecular geometry, bond length or bond distance is the average distance between nuclei of two bonded atoms in a molecule. It is a transferable property of a bond between atoms of fixed types, relatively independent of the rest of the molecule.
bond energy
[ /bɑnd ˈɛnərʤi/ ]
键能
📖 定义
In chemistry, bond energy (E) or bond enthalpy (H) is the measure of bond strength in a chemical bond. IUPAC defines bond energy as the average value of the gas-phase bond dissociation energies (usually at a temperature of 298 K) for all bonds of the same type within the same chemical species.
single bond
[ /ˈsɪŋgəl bɑnd/ ]
单键
📖 定义
In chemistry, a single bond is a chemical bond between two atoms involving two valence electrons. That is, the atoms share one pair of electrons where the bond forms. Therefore, a single bond is a type of covalent bond.
triple bond
[ /ˈtrɪpəl bɑnd/ ]
三键
📖 定义
A triple bond in chemistry is a chemical bond between two atoms involving six bonding electrons instead of the usual two in a covalent single bond. The most common triple bond that is between two carbon atoms can be found in alkynes.
double bond
[ /ˈdəbəl bɑnd/ ]
双键
📖 定义
A double bond in chemistry is a chemical bond between two chemical elements involving four bonding electrons instead of the usual two. The most common double bond that is between two carbon atoms can be found in alkenes.
potential energy
[ /pəˈtɛnʃəl ˈɛnərʤi/ ]
势能
📖 定义
Chemical potential energy is energy that is stored in atoms and the bonds between atoms and can be released by various chemical reactions. An example that most people are familiar with is the energy released when fossil fuels such as gasoline are burned.
kinetic energy
[ /kɪˈnɛtɪk ˈɛnərʤi/ ]
动能
📖 定义
Kinetic energy is a form of energy which is possessed by one during its relative motion.
internal energy
[ /ˌɪnˈtərnəl ˈɛnərʤi/ ]
内能
📖 定义
The total energy of a closed system, the sum of potential energy and its kinetic energy.
diatomic
[ /ˌdaɪəˈtɑmɪk/ ]
双原子的
📖 定义
Having two atoms in the molecule.
binary compounds
[ /ˈbaɪnəˌri ˈkɑmpaʊndz/ ]
二元化合物
📖 定义
In chemistry, a binary compound is something consisting of precisely two elements.
repulsive
[ /riˈpəlsɪv/ ]
排斥的 adj.
📖 定义
Relating to repulsion between physical objects.
intramolecular forces
[ /ˌɪntrəməlˈuːkɪkɔːl ˈfɔrsɪz/ ]
分子内作用力
📖 定义
An intramolecular force is any force that holds together the atoms making up a molecule or compound. They contain all types of chemical bond. They are stronger than intermolecular forces, which are present between atoms or molecules that are not actually bonded.
octet rule
[ /ɑkˈtɛt rul/ ]
八隅规则
📖 定义
A stable group of eight electrons occupying a single shell in an atom.
aqueous
[ /ˈeɪkwiəs/ ]
水溶液的 adj.
📖 定义
Of or containing water, typically as a solvent or medium.
insoluble
[ /ˌɪnˈsɑljəbəl/ ]
不可溶解的 adj.
📖 定义
(of a substance) Incapable of being dissolved.
metallic bonding
[ /məˈtælɪk ˈbɑndɪŋ/ ]
金属键
📖 定义
Metallic bonding arises from the electrostatic attractive force between conduction electrons (in the form of an electron cloud of delocalized electrons) and positively charged metal ions. It may be described as the sharing of free electrons among a lattice of positively charged ions (cations).
delocalized electrons
[ /dˈɛləkəlˌaɪzd ˌɪˈlɛktrɑnz/ ]
离域电子
📖 定义
In chemistry, delocalized electrons are electrons in a molecule, ion or solid metal that are not associated with a single atom or a covalent bond.
brittle
[ /ˈbrɪtəl/ ]
脆的 adj.
📖 定义
Hard but liable to break or shatter easily.
luster
[ /ˈləstər/ ]
金属光泽
📖 定义
A gentle sheen or soft glow, especially that of a partly reflective surface.
conductor
[ /kənˈdəktər/ ]
导体
📖 定义
A material or device that conducts or transmits heat, electricity, or sound, especially when regarded in terms of its capacity to do this.
alloy
[ /ˈæˌlɔɪ/ ]
合金
📖 定义
A metal made by combining two or more metallic elements, especially to give greater strength or resistance to corrosion.
Lewis diagram
[ /ˈluːɪs ˈdaɪəˌgræm/ ]
路易斯结构图
📖 定义
Lewis structures, also known as Lewis dot diagrams, Lewis dot formulas, Lewis dot structures, electron dot structures, or Lewis electron dot structures (LEDS), are diagrams that show the bonding between atoms of a molecule and the lone pairs of electrons that may exist in the molecule.
VSEPR model
[ /vˈɛspər ˈmɑdəl/ ]
VSEPR 模型
📖 定义
Valence Shell Electron Pair Repulsion (VSEPR) theory is a model used, in chemistry, to predict the geometry of individual molecules from the number of electron pairs surrounding their central atoms. It is also named Gillespie–Nyholm theory after its two main developers. The acronym "VSEPR" is pronounced either "ves-per" or "vuh-seh-per" by some chemists.
lone pairs
[ /loʊn pɛrz/ ]
孤电子对
📖 定义
In chemistry, a lone pair refers to a pair of valence electrons that are not shared with another atom and is sometimes called a non-bonding pair. Lone pairs are found in the outermost electron shell of atoms. They can be identified by using a Lewis structure. Electron pairs are therefore considered lone pairs if two electrons are paired but are not used in chemical bonding.
bond order
[ /bɑnd ˈɔrdər/ ]
键级
📖 定义
Bond order is the number of chemical bonds between a pair of atoms. For example, in diatomic nitrogen N≡N the bond order is 3, in acetylene H−C≡C−H the bond order between the two carbon atoms is also 3, and the C−H bond order is 1. Bond order gives an indication of the stability of a bond.
resonance
[ /ˈrɛzənəns/ ]
共振
📖 定义
In chemistry, resonance or mesomerism is a way of describing delocalized electrons within certain molecules or polyatomic ions where the bonding cannot be expressed by one single Lewis structure. A molecule or ion with such delocalized electrons is represented by several contributing structures (also called resonance structures or canonical structures).
formal charge
[ /ˈfɔrməl ʧɑrʤ/ ]
形式电荷 [注: 原PDF误作正式电荷]
📖 定义
In chemistry, a formal charge (FC) is the charge assigned to an atom in a molecule, assuming that electrons in all chemical bonds are shared equally between atoms, regardless of relative electronegativity.
Hybrid Orbital Theory
[ /ˈhaɪbrɪd ˈɔrbətəl ˈθɪri/ ]
杂化轨道理论
📖 定义
In chemistry, orbital hybridisation (or hybridization) is the concept of mixing atomic orbitals into new hybrid orbitals (with different energies, shapes, etc., than the component atomic orbitals) suitable for the pairing of electrons to form chemical bonds in valence bond theory.
hybridization
[ /ˌhaɪbrɪdaɪˈzeɪʃən/ ]
杂化
📖 定义
In chemistry, hybridisation (or hybridization) is the concept of mixing atomic orbitals into new hybrid orbitals (with different energies, shapes, etc., than the component atomic orbitals) suitable for the pairing of electrons to form chemical bonds in valence bond theory. Hybrid orbitals are very useful in the explanation of molecular geometry and atomic bonding properties.
Sigma bonds
[ /ˈsɪgmə bɑndz/ ]
sigma 键
📖 定义
In chemistry, sigma bonds (σ bonds) are the strongest type of covalent chemical bond. They are formed by head-on overlapping between atomic orbitals. Sigma bonding is most simply defined for diatomic molecules using the language and tools of symmetry groups. In this formal approach, a σ-bond is symmetrical with respect to rotation about the bond axis.
Pi bond (π bond)
[ /paɪ bɑnd/ ]
π 键
📖 定义
Pi bond. In chemistry, pi bonds (π bonds) are covalent chemical bonds where two lobes of an orbital on one atom overlap two lobes of an orbital on another atom.
tetrahedral
[ /ˌtɛtrəˈhidrəl/ ]
四面体
📖 定义
A solid having four plane triangular faces; a triangular pyramid.
trigonal pyramidal
[ /trˈɪɡənəl pərˈæmədəl/ ]
三角锥体
📖 定义
In chemistry, a trigonal pyramid is a molecular geometry with one atom at the apex and three atoms at the corners of a trigonal base. When all three atoms at the corners are identical, the molecule belongs to point group C3v. Some molecules and ions with trigonal pyramidal geometry are ammonia (NH3), xenon trioxide, XeO3, the chlorate ion, ClO3, and the sulfite ion, SO3.
bent
[ /bɛnt/ ]
V 型 adj.
📖 定义
Sharply curved or having an angle.
linear
[ /ˈlɪniər/ ]
线型 adj.
📖 定义
Arranged in or extending along a straight or nearly straight line.
isomer
[ /ˈaɪsəmər/ ]
同分异构体
📖 定义
Each of two or more compounds with the same formula but a different arrangement of atoms in the molecule and different properties.
electron domains
[ /ˌɪˈlɛktrɑn doʊˈmeɪnz/ ]
电子域
📖 定义
In chemistry, the electron domain refers to the number of lone pairs or bond locations around a particular atom in a molecule. Electron domains may also be called electron groups. Bond location is independent of whether the bond is a single, double or triple bond.
molten
[ /ˈmoʊltən/ ]
熔融 adj.
📖 定义
(especially of materials with a high melting point, such as metal and glass) Liquefied by heat.
exothermic
[ /ˌɛksoʊˈθərmɪk/ ]
放热的 adj.
📖 定义
(of a reaction or process) Accompanied by the release of heat.
ductile
[ /ˈdəktəl/ ]
可延展的 adj.
📖 定义
(of a metal) Able to be drawn out into a thin wire.
malleable
[ /ˈmæliəbəl/ ]
可塑的 adj.
📖 定义
(of a metal or other material) Able to be hammered or pressed permanently out of shape without breaking or cracking.
graphite
[ /ˈgræˌfaɪt/ ]
石墨
📖 定义
A gray crystalline allotropic form of carbon which occurs as a mineral in some rocks and can be made from coke. It is used as a solid lubricant, in pencils, and as a moderator in nuclear reactors.
semiconductor
[ /ˌsɛmɪkənˈdəktər/ ]
半导体
📖 定义
Semiconductors are crystalline or amorphous solids with distinct electrical characteristics. They are of high resistance-higher than typical resistance materials, but still of much lower resistance than insulators. Their resistance decreases as their temperature increases, which is behavior opposite to that of a metal.
transistor
[ /trænˈzɪstər/ ]
晶体管
📖 定义
A transistor is a semiconductor device used to amplify or switch electronic signals and electrical power. It is composed of semiconductor material with at least three terminals for connection to an external circuit. A voltage or current applied to one pair of the transistor's terminals changes the current through another pair of terminals.
molecular solids
[ /məˈlɛkjələr ˈsɑlədz/ ]
分子固体
📖 定义
A molecular solid is a type of solid in which molecules are held together by van der Waals forces rather than by ionic or covalent bonds.
net-ionic equation
[ /nˈɛtiːˈɑːnɪk ɪkˈweɪʒən/ ]
净离子方程式
📖 定义
A Net Ionic Equation is a chemical equation for a reaction which lists only those species participating in the reaction.
percent ionization
[ /pərˈsɛnt ˌaɪənəˈzeɪʃən/ ]
解离百分比
📖 定义
The percent ionization is the amount or percentage of a weak acid that exists as ions in a particular concentration. Strong acids and bases isolate altogether into ions in a solution, while weak acids and bases do not.
theoretical yield
[ /ˌθiərˈɛtɪkəl jild/ ]
理论产量
📖 定义
Maximum amount of a specified product that could be obtained from specified amounts of reactants, assuming complete consumption of limiting reactant according to only one reaction and complete recovery of product.
endpoint
[ /ˈɛndˌpɔɪnt/ ]
滴定终点
📖 定义
The point in a titration at which a reaction is complete, often marked by a color change.
molarity
[ /moʊˈlærəti/ ]
摩尔体积浓度
📖 定义
Molarity is the most commonly used term to describe the concentration of a solution. It is equal to the moles of solute divided by the liters of solution. The solute is defined as the substance being dissolved, while the solvent is the substance where the solute is dissolved (usually water).
synthesis
[ /ˈsɪnθəsəs/ ]
合成
📖 定义
Chemical synthesis means using chemical reactions to get a product, or several products. This happens by physical and chemical manipulations. Often, several different chemical reactions are used; one after another.
decomposition
[ /ˌdikəmpəˈzɪʃən/ ]
分解
📖 定义
Chemical decomposition, analysis or breakdown is the separation of a single chemical compound into its two or more elemental parts or to simpler compounds. Chemical decomposition is usually regarded and defined as the exact opposite of chemical synthesis.
Arrhenius Concept of Acids and Bases
[ /ɑːˈreɪniəs ˈkɑnsɛpt əv ˈæsədz ənd ˈbeɪsɪz/ ]
阿伦尼乌斯酸碱理论
📖 定义
In 1884, Ar Svante Arrhenius, a Swedish chemist proposed a new theory of acids and bases known as Arrhenius concept of acids and bases. According to Arrhenius concept: an acid is a substance which dissociates in an aqueous solution to give hydrogen ions.
Brønsted–Lowry Concept of Acids and Bases
[ /bˈiːr stˈɛnd ˈlaʊri ˈkɑnsɛpt əv ˈæsədz ənd ˈbeɪsɪz/ ]
质子酸碱论
📖 定义
Brønsted–Lowry theory, also called proton theory of acids and bases, a theory, introduced independently in 1923 by the Danish chemist Johannes Nicolaus Brønsted and the English chemist Thomas Martin Lowry, stating that any compound that can transfer a proton to any other compound is an acid, and the compound that accepts the proton is a base.
Lewis Concept of Acids and Bases
[ /ˈluːɪs ˈkɑnsɛpt əv ˈæsədz ənd ˈbeɪsɪz/ ]
路易斯酸碱理论
📖 定义
In 1923, American chemist Gilbert Newton Lewis proposed generalized definitions for acids that do not restrict them to compounds containing hydrogen but in terms of the structure of acids and bases. Lewis defined an acid as any molecular or ionic species that contains an atom capable of sharing a pair of electrons furnished by a base.
electron-pair acceptor
[ /ɪlˈɛktrəprˈeɪn əksˈɛptər/ ]
电子对接受体
📖 定义
An electron acceptor is a chemical entity that accepts electrons transferred to it from another compound. It is an oxidizing agent that, by virtue of its accepting electrons, is itself reduced in the process.
oxidation-reduction (redox) reaction
[ /ˌɑːksədˌɪziːtˈeɪʃən riˈækʃən/ ]
氧化还原反应
📖 定义
A redox reaction (reduction and oxidation reaction) is a reaction in which there is a transfer of electrons. When an element is reduced, it gains electrons and its oxidation number is reduced.
valence
[ /ˈveɪləns/ ]
化合价
📖 定义
In chemistry, the valence or valency of an element is a measure of its combining power with other atoms when it forms chemical compounds or molecules. The concept of valence was developed in the second half of the 19th century and was successful in explaining the molecular structure of inorganic and organic compounds.
oxidizing agent
[ /ˈɑksəˌdaɪzɪŋ ˈeɪʤənt/ ]
氧化剂
📖 定义
In chemistry, oxidizing agent has two meanings. In one sense, an oxidizing agent is a chemical species that removes an electron from another species. It is one component in an oxidation-reduction (redox) reaction. In the second sense, an oxidizing agent or an oxidizer is a chemical species that transfers electronegative atoms, usually oxygen, to a substrate.
reducing agent
[ /rɪˈdusɪŋ ˈeɪʤənt/ ]
还原剂
📖 定义
A reducing agent (also called a reductant or reducer) is an element or compound that loses (or "donates") an electron to another chemical species in a redox chemical reaction. Since the reducing agent is losing electrons, it is said to have been oxidized.
half-reaction
[ /hˌælfrˈeɪtʃɪkən/ ]
半反应
📖 定义
A half reaction is obtained by considering the change in oxidation states of individual substances involved in the redox reaction.
flask
[ /flæsk/ ]
瓶
📖 定义
A container for liquids.
precipitate
[ /prɪˈsɪpɪˌteɪt/ ]
沉淀 v.
📖 定义
A substance precipitated from a solution.
Endothermic
[ /ˌɛndoʊˈθərmɪk/ ]
吸热的 adj.
📖 定义
(of a reaction or process) Accompanied by or requiring the absorption of heat. The opposite of exothermic.
reaction coordinate
[ /riˈækʃən koʊˈɔrdəˌneɪt/ ]
反应坐标
📖 定义
In chemistry, a reaction coordinate is an abstract one-dimensional coordinate which represents progress along a reaction pathway. It is usually a geometric parameter that changes during the conversion of one or more molecular entities. In molecular dynamics simulations, a reaction coordinate is called collective variable.
thermodynamics
[ /θˌɜːrmədˈiːniːəsk/ ]
热动力学
📖 定义
Thermodynamics is a branch of physics concerned with heat and temperature and their relation to energy and work. It defines macroscopic variables, such as internal energy, entropy, and pressure that partly describe a body of matter or radiation.
electrode potential
[ /ˌɪˈlɛktroʊd pəˈtɛnʃəl/ ]
电极电势
📖 定义
The difference in electric potential between an electrode and the electrolyte with which it is in contact.
volt
[ /voʊlt/ ]
电压单位
📖 定义
One volt is defined as the difference in electric potential between two points of a conducting wire when an electric current of one ampere dissipates one watt of power between those points.
standard state condition
[ /ˈstændərd steɪt kənˈdɪʃən/ ]
标况
📖 定义
In chemistry, the standard state of a material (pure substance, mixture or solution) is a reference point used to calculate its properties under different conditions.
galvanic cells
[ /ɡælˈvænɪk sɛlz/ ]
原电池
📖 定义
A galvanic cell, or voltaic cell, named after Luigi Galvani, or Alessandro Volta respectively, is an electrochemical cell that derives electrical energy from spontaneous redox reactions taking place within the cell.
anode
[ /ˈæˌnoʊd/ ]
阳极 / (原电池)负极 [注: 发生氧化反应]
📖 定义
An anode is an electrode through which conventional current flows into a polarized electrical device. A common mnemonic is ACID for "anode current into device". The direction of (positive) electric current is opposite to the direction of electron flow: (negatively charged) electrons flow out the anode to the outside circuit.
cathode
[ /ˈkæˌθoʊd/ ]
阴极 / (原电池)正极 [注: 发生还原反应]
📖 定义
A cathode is the electrode from which a conventional current leaves a polarized electrical device. This definition is sometimes remembered using the mnemonic CCD for cathode current departs. A conventional current describes the direction in which positive electronic charges move. Electrons have a negative charge, so the movement of electrons is opposite to the conventional current flow.
intensive property
[ /ˌɪnˈtɛnsɪv ˈprɑpərti/ ]
强度性质/内涵性质
📖 定义
Physical properties of materials and systems can often be categorized as being either intensive or extensive quantities, according to how the property changes when the size (or extent) of the system changes. According to IUPAC, an intensive property is one whose magnitude is independent of the size of the system, whereas an extensive property changes as the amount of size of the material changes.
spontaneity
[ /ˌspɑntəˈniəti/ ]
自发性
📖 定义
A spontaneous process is one that occurs on its own, without any energy input from the outside.
Gibbs free energy
[ /gɪbz fri ˈɛnərʤi/ ]
吉布斯自由能
📖 定义
In thermodynamics, the Gibbs free energy (IUPAC recommended name: Gibbs energy or Gibbs function; also known as free enthalpy to distinguish it from Helmholtz free energy) is a thermodynamic potential that measures the maximum or reversible work that may be performed by a thermodynamic system at a constant temperature and pressure (isothermal, isobaric).
Nernst equation
[ /nˈɜːrnst ɪkˈweɪʒən/ ]
能斯特方程
📖 定义
In electrochemistry, the Nernst equation is an equation that relates the reduction potential of a half-cell (or the total voltage, i.e. the electromotive force, of the full cell) at any point in time to the standard electrode potential, temperature, activity, and reaction quotient of the underlying reactions and species used.
lithium-ion batteries
[ /lˈɪθiːəmjˌuːn ˈbætəriz/ ]
锂电池
📖 定义
The electrodes of a lithium-ion battery are made of lightweight lithium and carbon. Lithium is also a highly reactive element, meaning that a lot of energy can be stored in its atomic bonds. This translates into a very high energy density for lithium-ion batteries. Here is a way to get a perspective on the energy density. A typical lithium-ion battery can store 150 watt-hours of electricity in 1 kilogram of battery.
fuel cells
[ /fjuəl sɛlz/ ]
燃料电池
📖 定义
A fuel cell uses the chemical energy of hydrogen or another fuel to cleanly and efficiently produce electricity. If hydrogen is the fuel, electricity, water, and heat are the only products.
electrolytic cells
[ /ˌɪˌlɛktrəˈlɪtɪk sɛlz/ ]
电解池
📖 定义
An electrolytic cell is an electrochemical cell that undergoes a redox reaction when electrical energy is applied. It is most often used to decompose chemical compounds, in a process called electrolysis—the Greek word lysis means to break up. When electrical energy is added to the system, the chemical energy is increased.
electroplating
[ /ˌɪˈlɛktrəˌpleɪtɪŋ/ ]
电镀
📖 定义
Electroplating is a process that uses electric current to reduce dissolved metal cations so that they form a coherent metal coating on an electrode. The term is also used for electrical oxidation of anions onto a solid substrate, as in the formation silver chloride on silver wire to make silver/silver-chloride electrodes.
salt bridge
[ /sɔlt brɪʤ/ ]
盐桥
📖 定义
A salt bridge, in electrochemistry, is a laboratory device used to connect the oxidation and reduction half-cells of a galvanic cell (voltaic cell), a type of electrochemical cell. It maintains electrical neutrality within the internal circuit, preventing the cell from rapidly running its reaction to equilibrium.
reaction rate
[ /riˈækʃən reɪt/ ]
反应速率
📖 定义
The reaction rate (rate of reaction) or speed of reaction for a reactant or product in a particular reaction is intuitively defined as how fast or slow a reaction takes place. For example, the oxidative rusting of iron under Earth's atmosphere is a slow reaction that can take many years, but the combustion of cellulose in a fire is a reaction that takes place in fractions of a second.
instantaneous rate
[ /ˌɪnstənˈtæniəs reɪt/ ]
瞬时速度
📖 定义
The instantaneous rate of change measures the rate of change, or slope, of a curve at a certain instant. Thus, the instantaneous rate of change is given by the derivative.
collision model
[ /kəˈlɪʒən ˈmɑdəl/ ]
碰撞模型
📖 定义
A collision model is a model of the rate of a reaction showing how the rate is proportional to the number of collisions of reactant molecules.
transition state
[ /trænˈzɪʃən steɪt/ ]
过渡态
📖 定义
The transition state of a chemical reaction is a particular configuration along the reaction coordinate. It is defined as the state corresponding to the highest potential energy along this reaction coordinate. At this point, assuming a perfectly irreversible reaction, colliding reactant molecules always go on to form products. It is often marked with the double dagger symbol (‡).
activation energy
[ /ˌæktəˈveɪʃən ˈɛnərʤi/ ]
活化能
📖 定义
In chemistry, activation energy is a term introduced in 1889 by the Swedish scientist Svante Arrhenius to describe the minimum energy which must be available to a chemical system with potential reactants to result in a chemical reaction. Activation energy may also be defined as the minimum energy required to start a chemical reaction.
rate-determining step
[ /rˌætədmˈɪrɪŋθ stɛp/ ]
限速步骤
📖 定义
The rate determining step is the slowest step of a chemical reaction that determines the speed (rate) at which the overall reaction proceeds.
logarithm
[ /ˈlɑgərˌɪðəm/ ]
对数
📖 定义
In mathematics, the logarithm is the inverse operation to exponentiation. That means the logarithm of a number is the exponent to which another fixed value, the base, must be raised to produce that number. In simple cases the logarithm counts repeated multiplication. For example, the base 10 logarithm of 1000 is 3, as 10 to the power 3 is 1000; the multiplication is repeated three times.
rate constants
[ /reɪt ˈkɑnstənts/ ]
速率常数
📖 定义
The rate constant is a proportionality factor in the rate law of chemical kinetics that relates the molar concentration of reactants to reaction rate. It is also known as the reaction rate constant or reaction rate coefficient and is indicated in an equation by the letter k.
unit
[ /ˈjunɪt/ ]
单位
📖 定义
A quantity chosen as a standard in terms of which other quantities may be expressed. E.g. “a unit of measurement"
half-life
[ /hˈælflˌaɪf/ ]
半衰期
📖 定义
Half-life (t1⁄2) is the time required for the amount of something to fall to half its initial value. The term is very commonly used in nuclear physics to describe how quickly unstable atoms undergo decay, or how long stable atoms survive, and it is also used more generally of any type of exponential or non-exponential decay. The converse of half-life is doubling time.
unimolecular
[ /ˌʌnɪməlˈɑːkɪlər/ ]
单分子的 adj.
📖 定义
Consisting of or involving a single molecule.
reaction mechanism
[ /riˈækʃən ˈmɛkəˌnɪzəm/ ]
反应机制
📖 定义
In chemistry, a reaction mechanism is the step by step sequence of elementary reactions by which overall chemical change occurs. A chemical mechanism describes in detail exactly what takes place at each stage of an overall chemical reaction (transformation).
reaction intermediate
[ /riˈækʃən ˌɪnərˈmidiɪt/ ]
反应中间物
📖 定义
An intermediate or reaction intermediate is a substance formed during a middle step of a chemical reaction between reactants and the desired product. Intermediates tend to be extremely reactive and short-lived, so they represent a low concentration in a chemical reaction compared with the amount of reactants or products.
elementary step
[ /ˌɛləˈmɛnʧri stɛp/ ]
基元反应
📖 定义
An elementary process is also called elementary step or elementary reactions. It expresses how actually molecules or ions react with each other. The equation in an elementary step represents the reaction at the molecular level, not the overall reaction.
bimolecular reactions
[ /bɪməlˈuːkɪlər riˈækʃənz/ ]
双分子反应
📖 定义
Chemical reactions in which two particles participate in the elementary events.
Maxwell-Boltzmann thermal distribution
[ /mˌækswˈɜːrləstənt ˈθərməl ˌdɪstrəˈbjuʃən/ ]
波兹曼分布
📖 定义
The Maxwell-Boltzmann equation, which forms the basis of the kinetic theory of gases, defines the distribution of speeds for a gas at a certain temperature. From this distribution function, the most probable speed, the average speed, and the root-mean-square speed can be derived.
bonds forming
[ /bɑndz ˈfɔrmɪŋ/ ]
键的形成
📖 定义
Common types of bonds include ionic, covalent and metallic bonds. The formation of the bond links the two atoms through the strong attractive forces, using a bond, a region where the electrons of the atoms interact with one another.
combustion
[ /kəmˈbəsʧən/ ]
燃烧
📖 定义
Combustion /kəmˈbʌs.tʃən/ or burning is a high-temperature exothermic redox chemical reaction between a fuel and an oxidant, usually atmospheric oxygen that produces oxidized, often gaseous products, in a mixture termed as smoke. Combustion in a fire produces a flame, and the heat produced can make combustion self-sustaining.
activated complex
[ /ˈæktɪˌveɪtɪd ˈkɑmplɛks/ ]
活化复合物
📖 定义
In chemistry an activated complex is defined by the International Union of Pure and Applied Chemistry (IUPAC) as "that assembly of atoms which corresponds to an arbitrary infinitesimally small region at or near the col (saddle point) of a potential energy surface". In other words, it refers to a collection of intermediate structures in a chemical reaction that persist while bonds are breaking and new bonds are forming. It therefore represents not one defined state, but rather a range of transient configurations that a collection of atoms passes through in between clearly defined products and reactants.
magnitude
[ /ˈmægnəˌtud/ ]
级数，量级
📖 定义
The great size or extent of something.
liter
[ /ˈlitər/ ]
升
📖 定义
The litre (SI spelling) or liter (American spelling) (symbols L or l, sometimes abbreviated ltr) is an SI accepted metric system unit of volume equal to 1 cubic decimeter (dm3), 1,000 cubic centimeters (cm3) or 1/1,000 cubic metre. A cubic decimetre (or litre) occupies a volume of 10 cm×10 cm×10 cm (see figure) and is thus equal to one-thousandth of a cubic metre.
exponent
[ /ˈɛkˌspoʊnənt/ ]
指数
📖 定义
A quantity representing the power to which a given number or expression is to be raised, usually expressed as a raised symbol beside the number or expression (e.g. 3 in 23 = 2 × 2 × 2).
multi-step
[ /mˈʌltiːstˌɛk/ ]
多步骤的 adj.
📖 定义
Involving two or more distinct steps or stages.
decomposition
[ /ˌdikəmpəˈzɪʃən/ ]
分解
📖 定义
Chemical decomposition, analysis or breakdown is the separation of a single chemical compound into its two or more elemental parts or to simpler compounds. Chemical decomposition is usually regarded and defined as the exact opposite of chemical synthesis.
molar concentration
[ /mˈoʊlər ˌkɑnsənˈtreɪʃən/ ]
摩尔浓度
📖 定义
Molar concentration, also called molarity, amount concentration or substance concentration, is a measure of the concentration of a solute in a solution, or of any chemical species, in terms of amount of substance in a given volume. A commonly used unit for molar concentration used in chemistry is mol/L. A solution of concentration 1 mol/L is also denoted as 1 molar (1 M).
reaction intermediates
[ /riˈækʃən ˌɪnərˈmidiəts/ ]
反应中间物
📖 定义
An intermediate or reaction intermediate is a substance formed during a middle step of a chemical reaction between reactants and the desired product. Intermediates tend to be extremely reactive and short-lived, so they represent a low concentration in a chemical reaction compared with the amount of reactants or products.
bond breaking
[ /bɑnd ˈbreɪkɪŋ/ ]
化学键断裂
📖 定义
Bond breaking and bond forming occur during a chemical reaction. The energy changes in chemical reactions are caused by bond breaking and bond forming. Breaking a bond is endothermic. Energy is taken in to break a chemical bond.
carbonyl group
[ /kˈɑːrbənəl grup/ ]
羰基 [注: 原PDF误作羟基]
📖 定义
In organic chemistry, a carbonyl group is a functional group composed of a carbon atom double-bonded to an oxygen atom: C=O. It is common to several classes of organic compounds, as part of many larger functional groups. A compound containing a carbonyl group is often referred to as a carbonyl compound.
Haber process
[ /ˈheɪbər ˈprɔˌsɛs/ ]
哈伯博斯制氨法
📖 定义
The Haber process, also called the Haber–Bosch process, is an artificial nitrogen fixation process and is the main industrial procedure for the production of ammonia today. It is named after its inventors, the German chemists Fritz Haber and Carl Bosch, who developed it in the first half of the 20th century.
in motion
[ /ɪn ˈmoʊʃən/ ]
动态中
📖 定义
Not static; moving.
average kinetic energy
[ /ˈævərɪʤ kɪˈnɛtɪk ˈɛnərʤi/ ]
平均动能
📖 定义
The average kinetic energy of the particles of a substance is determined by the temperature of the medium, using the equation for an ideal gas. If the temperature is unknown, then the average speed and mass of the particles are utilized to determine the average kinetic energy.
kinetic energy
[ /kɪˈnɛtɪk ˈɛnərʤi/ ]
动能
📖 定义
Kinetic energy is the energy an object possesses due to its motion. An object of mass m moving at velocity v has a kinetic energy equal to ½mv2.
thermal equilibrium
[ /ˈθərməl ˌiːkwɪˈlɪbriəm/ ]
热平衡
📖 定义
Thermal equilibrium is when the temperature of a system or organism is equal to the temperature of its surroundings. It is part of the zeroth law of thermodynamics. The zeroth law is that if 2 things are at the same temperature, no heat will flow between them.
specific heat capacity
[ /spɪˈsɪfɪk hit kəˈpæsɪti/ ]
比热容
📖 定义
The quantity of heat that will raise the temperature of 1g of a substance by 1 °C, usually in units of cal g-1 °C-1 or J g-1 °C-1.
heat capacity
[ /hit kəˈpæsɪti/ ]
热容
📖 定义
The amount of energy required to raise the temperature of an object by one degree Celsius (or Kelvin). It is represented by the symbol c and is given in units of J/K.
glycerol
[ /ˈglɪsərˌoʊl/ ]
甘油
📖 定义
A clear, colorless, viscous, sweet-tasting liquid belonging to the alcohol family of organic compounds.
trichloropropane
[ /trˌɪklɑːrˈɔːpərn/ ]
三氯丙烷
📖 定义
Trichloropropane is a synthetic chemical that is also known as allyl trichloride, glycerol trichlorohydrin, and trichlorohydrin. It is a colorless, heavy liquid with a sweet but strong odor. It evaporates very quickly and small amounts dissolve in water.
enthalpy of combustion
[ /ˈɛnθəlpi əv kəmˈbəsʧən/ ]
燃烧焓
📖 定义
The standard enthalpy of combustion is the enthalpy change when one mole of a reactant completely burns in excess oxygen under standard thermodynamic conditions (although experimental values are usually obtained under different conditions and subsequently adjusted).
thermodynamics
[ /θˌɜːrmədˈiːniːəsk/ ]
热动力学
📖 定义
Thermodynamics is a branch of physics concerned with heat and temperature and their relation to energy and work. It defines macroscopic variables, such as internal energy, entropy, and pressure, that partly describe a body of matter or radiation.
electromagnetism
[ /ˌɪˌlɛktroʊˈmægnəˌtɪzəm/ ]
电磁
📖 定义
Electromagnetism is a branch of physics which involves the study of the electromagnetic force, a type of physical interaction that occurs between electrically charged particles. The electromagnetic force usually shows electromagnetic fields, such as electric fields, magnetic fields, and light. The electromagnetic force is one of the four fundamental interactions in nature.
heat exchange
[ /hit ɪksˈʧeɪnʤ/ ]
热交换
📖 定义
Transfer of heat between two or more objects.
The Laws of Thermodynamics
[ /ðə lɔz əv θˌɜːrmədˈiːniːəsk/ ]
热力学定理
📖 定义
The four laws of thermodynamics define fundamental physical quantities (temperature, energy, and entropy) that characterize thermodynamic systems. The laws describe how these quantities behave under various circumstances, and forbid certain phenomena (such as perpetual motion).
phase transition
[ /feɪz trænˈzɪʃən/ ]
相变
📖 定义
A phase transition is the transformation of a thermodynamic system from one phase or state of matter to another one by heat transfer. The term is most commonly used to describe transitions between solid, liquid and gaseous states of matter, and, in rare cases, plasma. A phase of a thermodynamic system and the states of matter have uniform physical properties.
condense
[ /kənˈdɛns/ ]
冷凝 v.
📖 定义
Change or cause to change from a gas or vapor to a liquid.
enthalpy of vaporization
[ /ˈɛnθəlpi əv veɪpərəˈzeɪʃən/ ]
蒸发焓
📖 定义
The enthalpy of vaporization, (symbol ∆Hvap) also known as the (latent) heat of vaporization or heat of evaporation, is the energy (enthalpy) that must be added to the substance, typically a liquid, to transform a quantity of that substance into a gas. The enthalpy of vaporization is a function of the pressure at which that transformation takes place.
work
[ /wərk/ ]
功
📖 定义
In physics, a force is said to do work if, when acting on a body, there is a displacement of the point of application in the direction of the force. For example, when a ball is held above the ground and then dropped, the work done on the ball as it falls is equal to the weight of the ball (a force) multiplied by the distance to the ground (a displacement).
heat of reaction
[ /hit əv riˈækʃən/ ]
反应热
📖 定义
The heat of reaction (also known and enthalpy of reaction) is the change in the enthalpy of a chemical reaction that occurs at a constant pressure. It is a thermodynamic unit of measurement useful for calculating the amount of energy per mole either released or produced in a reaction.
calorimeter
[ /kəlˈɔːrəmˌɛtər/ ]
热量计
📖 定义
A calorimeter is an object used for calorimetry, or the process of measuring the heat of chemical reactions or physical changes as well as heat capacity. Differential scanning calorimeters, isothermal microcalorimeters, titration calorimeters and accelerated rate calorimeters are among the most common types.
piston
[ /ˈpɪstən/ ]
活塞
📖 定义
A disk or short cylinder fitting closely within a tube in which it moves up and down against a liquid or gas, used in an internal combustion engine to derive motion, or in a pump to impart motion.
cylinder
[ /ˈsɪlɪndər/ ]
圆筒/气缸
📖 定义
The piston chamber in an engine; a chamber in a pump from which the piston expels the fluid.
bucket
[ /ˈbəkɪt/ ]
桶
📖 定义
A roughly cylindrical open container, typically made of metal or plastic, with a handle, used to hold and carry liquids or other material.
bond enthalpies
[ /bɑnd ɪnθˈɑːlpiːz/ ]
键焓
📖 定义
The bond enthalpy is the energy required to break a chemical bond. It is usually expressed in units of kJ mol-1, measured at 298 K. The exact bond enthalpy of a particular chemical bond depends upon the molecular environment in which the bond exists. Therefore, bond enthalpy values given in chemical data books are averaged values.
isolated system
[ /ˈaɪsəˌleɪtɪd ˈsɪstəm/ ]
隔离系统
📖 定义
An isolated system obeys the conservation law that its total energy–mass stays constant. Most often, in thermodynamics, matter and energy are treated as separately conserved.
ozone
[ /ˈoʊˌzoʊn/ ]
臭氧
📖 定义
Ozone, or trioxygen, is an inorganic molecule with the chemical formula O3. It is a pale blue gas with a distinctively pungent smell. It is an allotrope of oxygen that is much less stable than the diatomic allotrope O2, breaking down in the lower atmosphere to O2 or dioxygen. Ozone is formed from dioxygen by the action of ultraviolet light (UV) and electrical discharges within the Earth's atmosphere. It is present in very low concentrations throughout the latter, with its highest concentration high in the ozone layer of the stratosphere, which absorbs most of the Sun's ultraviolet (UV) radiation.
surroundings
[ /sərˈaʊndɪŋz/ ]
环境
📖 定义
The system is the part of the universe we wish to focus our attention on. In the world of chemistry, the system is the chemical reaction, and the surroundings are everything else in this universe.
open system
[ /ˈoʊpən ˈsɪstəm/ ]
开放系统
📖 定义
An open system can transfer both energy and matter to and from the surroundings.
closed system
[ /kloʊzd ˈsɪstəm/ ]
封闭系统
📖 定义
A closed system is one where energy can be transferred to the surroundings but matter cannot.
dipole-induced dipole force
[ /daɪpˈɑːlədʒənds ˈdaɪˌpoʊl fɔrs/ ]
偶极-诱导偶极作用力 [注: 原PDF误作偶极-偶极]
📖 定义
A dipole-induced dipole attraction is a weak attraction that results when a polar molecule induces a dipole in an atom or in a nonpolar molecule by disturbing the arrangement of electrons in the nonpolar species.
dipole moment
[ /ˈdaɪˌpoʊl ˈmoʊmənt/ ]
偶极矩
📖 定义
A measure of the polarity in a chemical bond or molecule, equal to the product of one charge and the distance between the charges.
nonane
[ /nˈɑːnən/ ]
壬烷;
📖 定义
A colorless liquid hydrocarbon of the alkane series, present in petroleum spirit.
repulsions
[ /riːpˈʌlʃənz/ ]
排斥力
📖 定义
A force under the influence of which objects tend to move away from each other, e.g. through having the same magnetic polarity or electric charge.
hydrogen bonding
[ /ˈhaɪdrəʤən ˈbɑndɪŋ/ ]
氢键
📖 定义
The definition of hydrogen bond is a chemical bond between the hydrogen atom and an electronegative atom. An example of hydrogen bond is water molecules bonding together in the form of ice.
electrostatic forces
[ /ˌɪˌlɛktroʊˈstætɪk ˈfɔrsɪz/ ]
静电力
📖 定义
Electrostatic force is the force that occurs between electrically charged objects. The Force existing between two charged particles is known as electrostatic force. Example of it would be: plastic rubber.
hydration energy
[ /haɪˈdreɪʃən ˈɛnərʤi/ ]
水合能
📖 定义
Hydration energy (also hydration enthalpy) is the amount of energy released when one mole of ions undergo hydration. It is a special case of dissolution energy, with the solvent being water. For example, upon dissolving a salt in water, the outermost ions (those at the edge of the lattice) move away from the lattice and become covered with the neighboring water molecules.
polarizable
[ /pˈoʊlərəzəz/ ]
可被极化的 adj.
📖 定义
Polarizability is the ability to form instantaneous dipoles. It is a property of matter. Polarizabilities determine the dynamical response of a bound system to external fields, and provide insight into a molecule's internal structure.
thymine
[ /ˈθaɪmiːn/ ]
胸腺嘧啶
📖 定义
A compound which is one of the four constituent bases of nucleic acids. A pyrimidine derivative, it is paired with adenine in double-stranded DNA.
adenine
[ /ˈædənɪn/ ]
腺嘌呤
📖 定义
A compound which is one of the four constituent bases of nucleic acids. A purine derivative, it is paired with thymine in double-stranded DNA.
base pairs
[ /beɪs pɛrz/ ]
碱基对
📖 定义
A base pair (bp) is a unit consisting of two nucleobases bound to each other by hydrogen bonds. They form the building blocks of the DNA double helix, and contribute to the folded structure of both DNA and RNA.
DNA strand
[ /ˈdiˌɛˈneɪ strænd/ ]
DNA 链
📖 定义
A long linear polymer found in the nucleus of a cell and formed from nucleotides and shaped like a double helix; associated with the transmission of genetic information.
electron cloud
[ /ˌɪˈlɛktrɑn klaʊd/ ]
电子云
📖 定义
An electron cloud is the region of negative charge surrounding an atomic nucleus that is associated with an atomic orbital. It is defined mathematically, describing a region with a high probability of containing electrons.
disorder
[ /dɪˈsɔrdər/ ]
混乱/无序
📖 定义
A lack of order or regular arrangement; disarray; confusion.
dehydration of ethanol
[ /ˌdihaɪˈdreɪʃən əv ˈɛθəˌnɔl/ ]
乙醇脱水
📖 定义
The dehydration of ethanol to give ethene. Ethanol is heated with an excess of concentrated sulphuric acid at a temperature of 170°C. The gases produced are passed through sodium hydroxide solution to remove the carbon dioxide and sulphur dioxide produced from side reactions.
dissolution
[ /ˌdɪsəˈluʃən/ ]
溶解
📖 定义
The dissolution of gases, liquids, or solids into a liquid or other solvent is a process by which these original states become solutes (dissolved components), forming a solution of the gas, liquid, or solid in the original solvent.
thermodynamic
[ /θˌɜːrmədiːnˈæmɪk/ ]
热力的 adj.
📖 定义
The branch of physical science that deals with the relations between heat and other forms of energy (such as mechanical, electrical, or chemical energy), and, by extension, of the relationships between all forms of energy.
spontaneous
[ /spɑnˈteɪniəs/ ]
自发的 adj.
📖 定义
(of a process or event) Occurring without apparent external cause.
barrier
[ /ˈbɛriər/ ]
障碍
📖 定义
Anything serving to obstruct passage or to maintain separation.
reaction quotient (Qr)
[ /riˈækʃən kˈwoʊʃənt/ ]
反应商
📖 定义
In chemistry, a reaction quotient (Qr) is a function of the activities or concentrations of the chemical species involved in a chemical reaction. In the special case that the reaction is at equilibrium the reaction quotient is constant and equal to the equilibrium constant which appears in the expression of the law of mass action.
physical state
[ /ˈfɪzɪkəl steɪt/ ]
物理状态
📖 定义
In physics, a state of matter is one of the distinct forms in which matter can exist. Four states of matter are observable in everyday life: solid, liquid, gas, and plasma. Many other states are known to exist, such as glass or liquid crystal, and some only exist under extreme conditions, such as Bose–Einstein condensates, neutron-degenerate matter, and quark-gluon plasma, which only occur, respectively, in situations of extreme cold, extreme density, and extremely high-energy. Some other states are believed to be possible but remain theoretical for now.
numerator
[ /nˈuːmərˌeɪtər/ ]
分子
📖 定义
The part of a fraction that is above the line and signifies the number to be divided by the denominator.
denominator
[ /dɪˈnɑməˌneɪtər/ ]
分母
📖 定义
The number below the line in a common fraction; a divisor.
concentration
[ /ˌkɑnsənˈtreɪʃən/ ]
浓度
📖 定义
The relative amount of a given substance contained within a solution or in a particular volume of space; the amount of solute per unit volume of solution.
solubility product constant
[ /ˌsɑːljʊˈbɪləti ˈprɑdəkt ˈkɑnstənt/ ]
溶度积常数
📖 定义
Solubility product constant is simplified equilibrium constant (Ksp) defined for equilibrium between a solids and its respective ions in a solution. Its value indicates the degree to which a compound dissociates in water.
condensation
[ /ˌkɑndənˈseɪʃən/ ]
缩合/冷凝
📖 定义
1. A reaction in which two molecules combine to form a larger molecule, producing a small molecule such as H2O as a byproduct. 2. It can also mean the conversion of a vapor or gas to a liquid.
molarity
[ /moʊˈlærəti/ ]
摩尔体积浓度
📖 定义
The number of moles of solute per liter of solution.
diprotic acid
[ /daɪprˈɑːtɪk ˈæsəd/ ]
二元酸
📖 定义
Any acid with two hydrogen atoms in its molecule that are capable of being released or ionized in water, such as sulphuric acid and carbonic acid.
triprotic acid
[ /traɪprˈoʊtɪk ˈæsəd/ ]
三元酸
📖 定义
An acid that has three ionizable hydrogen atoms in each molecule.
stepwise dissociation
[ /stˈɛpwˌaɪz dɪˌsoʊsiˈeɪʃən/ ]
分步电离
📖 定义
A stepwise reaction is a chemical reaction with one or more reaction intermediates and involving at least two consecutive elementary reactions.
oxyacid
[ /ˈɑːksədˌeɪsɪk/ ]
含氧酸
📖 定义
An oxyacid, or oxoacid, is an acid that contains oxygen. Specifically, it is a compound that contains hydrogen, oxygen, and at least one other element, with at least one hydrogen atom bond to oxygen that can dissociate to produce the H+ cation and the anion of the acid.
spectator ion
[ /ˈspɛkteɪtər aɪən/ ]
不相关离子
📖 定义
A spectator ion is an ion that exists as a reactant and a product in a chemical equation.
amphiprotic
[ /ˌæmfɪˈprɑːtɪk/ ]
两性的 adj.
📖 定义
In chemistry, an amphoteric compound is a molecule or ion that can react both as an acid as well as a base. Many metals (such as copper, zinc, tin, lead, aluminium, and beryllium) form amphoteric oxides or hydroxides. Amphoterism depends on the oxidation states of the oxide. Al2O3 is an example of an amphoteric oxide.
equivalence point
[ /ɪkˈwɪvələns pɔɪnt/ ]
当量点
📖 定义
The equivalence point, or stoichiometric point, of a chemical reaction is the point at which chemically equivalent quantities of bases and acids have been mixed. In other words, the moles of acid are equivalent to the moles of base, according to the equation (this does not necessarily imply a 1:1 molar ratio of acid:base, merely that the ratio is the same as in the equation). It can be found by means of an indicator, for example phenolphthalein or methyl orange.
pH
[ /ˈpiˈeɪʧ/ ]
酸碱度
📖 定义
A figure expressing the acidity or alkalinity of a solution on a logarithmic scale on which 7 is neutral, lower values are more acid and higher values more alkaline.
dissolution
[ /ˌdɪsəˈluʃən/ ]
融化，溶解
📖 定义
The dissolution of gases, liquids, or solids into a liquid or other solvent is a process by which these original states become solutes (dissolved components), forming a solution of the gas, liquid, or solid in the original solvent.
Lewis electron-dot diagrams
[ /ˈluːɪs ɪlˈɛktrəndˌɑːt ˈdaɪəˌgræmz/ ]
路易斯点式
📖 定义
Lewis Electron Dot Diagrams are used to visually depict bonding by representing valence electrons as dots surrounding an elemental symbol. These dots can be on any of the four sides of the symbol, each side representing a different orbital.
| 化学单词 (Term) | 国际音标 (IPA) | 中文释义 (Translation) | 英文详细定义 (Definition) | 页码 |
|---|---|---|---|---|
| atomic mass (ma) | [ /əˈtɑmɪk mæs/ ] | 原子质量 |
The mass of an atom of a chemical element expressed in atomic mass units. It is approximately equivalent to the number of protons and neutrons in the atom (the mass number) or to the average number allowing for the relative abundances of different isotopes.
|
P.1 |
| average atomic mass | [ /ˈævərɪʤ əˈtɑmɪk mæs/ ] | 相对原子质量 |
The average atomic mass of carbon is 12.011. This is a weighted average based on three forms (isotopes) of carbon with different natural abundances. Carbon 12 has an atomic mass of 12.00 (carbon 12 is a special case because its mass is defined to be exactly 12 atomic mass units) and a natural abundance of 0.9893.
|
P.1 |
| mass units (symbol: u, or Da) | [ /mæs ˈjunɪts ˈsɪmbəl ju ər ˈdiˈeɪ/ ] | 原子质量单位 |
The unified atomic mass unit or Dalton (symbol: u, or Da) is a standard unit of mass that quantifies mass on an atomic or molecular scale (atomic mass). One unified atomic mass unit is approximately the mass of one nucleon (either a single proton or neutron) and is numerically equivalent to 1 g/mol.
|
P.1 |
| proton | [ /ˈproʊˌtɑn/ ] | 质子 |
A stable subatomic particle occurring in all atomic nuclei, with a positive electric charge equal in magnitude to that of an electron, but of opposite sign.
|
P.1 |
| neutron | [ /ˈnuˌtrɑn/ ] | 中子 |
The neutron is a subatomic particle, symbol n or n0, with no net electric charge and a mass slightly larger than that of a proton. Protons and neutrons constitute the nuclei of atoms.
|
P.1 |
| mass number | [ /mæs ˈnəmbər/ ] | 质量数 |
The mass number (A), also called atomic mass number or nucleon number, is the total number of protons and neutrons (together known as nucleons) in an atomic nucleus. It determines the atomic mass of atoms. Because protons and neutrons both are baryons, the mass number A is identical with the baryon number B as of the nucleus as of the whole atom or ion.
|
P.1 |
| isotopic mass | [ /ˌaɪsəˈtɑːpɪk mæs/ ] | 同位素质量 |
The atomic mass (relative isotopic mass) is defined as the mass of a single atom, which can only be one isotope (nuclide) at a time, and is not an abundance-weighted average, as in the case of relative atomic mass/atomic weight.
|
P.1 |
| property | [ /ˈprɑpərti/ ] | 性质 |
A property or characteristic of a substance that is observed during a reaction in which the chemical composition or identity of the substance is changed: Combustibility is an important chemical property to consider when choosing building materials.
|
P.1 |
| composition | [ /ˌkɑmpəˈzɪʃən/ ] | 组成 |
The nature of something's ingredients or constituents; the way in which a whole or mixture is made up.
|
P.1 |
| element | [ /ˈɛləmənt/ ] | 元素 |
Elements are substances that cannot be decomposed into simpler substances. On the molecular level, each element is composed of only one kind of atom.
|
P.1 |
| compound | [ /ˈkɑmpaʊnd/ ] | 化合物 |
Compounds are substances composed of two or more elements; they contain two or more kinds of atoms.
|
P.1 |
| Mixture | [ /ˈmɪksʧər/ ] | 混合物 |
Mixtures are combinations of two or more substances in which each substance retains its chemical identity.
|
P.1 |
| molecule | [ /ˈmɑləˌkjul/ ] | 分子 |
A molecule is an entity composed of two or more atoms with the atoms attached to one another in a specific way.
|
P.1 |
| percent composition | [ /pərˈsɛnt ˌkɑmpəˈzɪʃən/ ] | 组成百分比 |
Percent composition is the term used to describe the percent by mass of each element in a compound. It is typically found using the molar mass values for both the elements in the compound and the compound itself.
|
P.1 |
| empirical formula | [ /ˌɛmˈpɪrɪkəl ˈfɔrmjələ/ ] | 经验式 |
In chemistry, the empirical formula of a chemical compound is the simplest positive integer ratio of atoms present in a compound. A simple example of this concept is that the empirical formula of sulfur monoxide, or SO, would simply be SO, as is the empirical formula of disulfur dioxide, S2O2.
|
P.1 |
| molar ratio | [ /mˈoʊlər ˈreɪʃiˌoʊ/ ] | 摩尔比例 |
Molar ratio is the proportion of one substance to another in a given chemical reaction. It is the ratio of their coefficients in the chemical equation.
|
P.1 |
| molecular formula | [ /məˈlɛkjələr ˈfɔrmjələ/ ] | 分子式 |
Molecular Formula. The molecular formula is an expression of the number and type of atoms that are present in a single molecule of a substance. It represents the actual formula of a molecule. Subscripts after element symbols represent the number of atoms.
|
P.1 |
| whole-number | [ /hˈoʊlənbˌaʊmər/ ] | 整数 |
A number without fractions; an integer.
|
P.2 |
| monoprotic acid | [ /mˌɑːnəprˈɑːtɪk ˈæsəd/ ] | 一元酸 [注: 原PDF作单元酸] |
A monoprotic acid is an acid that donates only one proton or hydrogen atom per molecule to an aqueous solution. This is in contrast to acids capable of donating more than one proton or hydrogen, which are called polypro tic acids.
|
P.2 |
| Mole | [ /moʊl/ ] | 摩尔 |
Moles are small mammals adapted to a subterranean lifestyle. They have cylindrical bodies; velvety fur; very small, inconspicuous ears and eyes; reduced hind limbs; and short, powerful forelimbs with large paws adapted for digging.
|
P.2 |
| Avogadro’s Number | [ /ˌævəˈɡɑːdroʊ ɛs ˈnəmbər/ ] | 阿伏伽德罗常数 |
In chemistry and physics, the Avogadro constant is the number of constituent particles, usually atoms or molecules, that are contained in the amount of substance given by one mole. Thus, it is the proportionality factor that relates the molar mass of a compound to the mass of a sample.
|
P.2 |
| stoichiometry | [ /ˌstɔɪkiˈɑːmətri/ ] | 化学计量学 / 化学计量 |
Stoichiometry /ˌstɔɪkiˈɒmᵻtri/ is the calculation of relative quantities of reactants and products in chemical reactions. Stoichiometry is founded on the law of conservation of mass where the total mass of the reactants equals the total mass of the products leading to the insight that the relations among quantities of reactants and products typically form a ratio of positive integers.
|
P.2 |
| Molar Mass | [ /mˈoʊlər mæs/ ] | 摩尔质量 |
In chemistry, the molar mass M is a physical property defined as the mass of a given substance (chemical element or chemical compound) divided by the amount of substance. The base SI unit for molar mass is kg/mol.
|
P.2 |
| conversion factors | [ /kənˈvərʒən ˈfæktərz/ ] | 转换因子 |
The easiest way to do stoichiometric calculations involves using conversion factors. A conversion factor is a ratio (or fraction) which represents the relationship between two different units. A conversion factor is ALWAYS equal to 1.
|
P.2 |
| balanced chemical equations | [ /ˈbælənst ˈkɛmɪkəl ɪkˈweɪʒənz/ ] | 平衡的化学方程式 |
A balanced chemical equation is when both the products and the reactants are balanced, or have the same number of atoms on each side of the equation.
|
P.2 |
| dissolve | [ /dɪˈzɑlv/ ] | 溶解 |
In science, dissolve means forming strong bonds between molecules of solute &solvent to form a complete solution which cannot be separated by simple processes like filtration.
|
P.2 |
| density | [ /ˈdɛnsɪti/ ] | 密度 |
The density, or more precisely, the volumetric mass density, of a substance is its mass per unit volume. The symbol most often used for density is ρ (the lower case Greek letter rho), although the Latin letter D can also be used.
|
P.2 |
| Coulomb’s law | [ /ˈkuːlɑːm ɛs lɔ/ ] | 库仑定律 |
Coulomb's law or Coulomb's inverse-square law, is a law of physics that describes force interacting between static electrically charged particles, where ke is Coulomb's constant, q1 and q2 are the signed magnitudes of the charges, the scalar r is the distance between the charges.
|
P.2 |
| ionic solid | [ /ˌaɪˈɑnɪk ˈsɑləd/ ] | 离子晶体 |
Ionic solids are solids composed of oppositely charged ions. They consist of positively charged cations and negatively charged anions .When Ionic Solids are dissolved in water the cations and the anions separate, they become free to move about in the water allowing the solution to conduct electrical current.
|
P.2 |
| lattice energy | [ /ˈlætəs ˈɛnərʤi/ ] | 晶格能 |
Lattice energy, the energy needed to completely separate an ionic solid, such as common table salt, into gaseous ions (also the energy released in the reverse process). Lattice energy is usually measured in kilojoules per mole (1 mole = 6.0221367 * 1023).
|
P.2 |
| ionization energy | [ /ˌaɪənəˈzeɪʃən ˈɛnərʤi/ ] | 电离能 |
The ionization energy (IE) is qualitatively defined as the amount of energy required to remove the most loosely bound electron of an isolated gaseous atom to form a cation, where X is any atom or molecule capable of being ionized, X is that atom or molecule with an electron removed, and e is the removed electron. This is an endothermic process.
|
P.2 |
| electron | [ /ˌɪˈlɛktrɑn/ ] | 电子 |
A stable subatomic particle with a charge of negative electricity, found in all atoms and acting as the primary carrier of electricity in solids.
|
P.3 |
| first ionization energy | [ /fərst ˌaɪənəˈzeɪʃən ˈɛnərʤi/ ] | 第一电离能 |
By definition, the first ionization energy of an element is the energy needed to remove the outermost, or highest energy, electron from a neutral atom in the gas phase.
|
P.3 |
| second ionization energy | [ /ˈsɛkənd ˌaɪənəˈzeɪʃən ˈɛnərʤi/ ] | 第二电离能 |
Second ionization energy is the energy needed to remove a second electron from an atom after one has already been removed. It always takes energy to remove electrons from atoms, although the amount of energy varies greatly. This process is known as ionization, which makes charged ions from neutral atoms.
|
P.3 |
| Aufbau Principle | [ /ˈaʊfbaʊ ˈprɪnsəpəl/ ] | 构筑原理 |
The Aufbau Principle, from the German Aufbauprinzip (building-up principle), also called the Aufbau Rule, states that in the ground state of an atom or ion, electrons fill atomic orbitals of the lowest available energy levels before occupying higher levels.
|
P.3 |
| Pauli Exclusion Principle | [ /ˈpaʊli ɪkˈskluʒən ˈprɪnsəpəl/ ] | 泡利不相容原理 |
The Pauli exclusion principle is the quantum mechanical principle that states that two identical fermions (particles with half-integer spin) cannot occupy the same quantum state simultaneously.
|
P.3 |
| Hund’s Rule | [ /hʊnd ɛs rul/ ] | 洪特规则 |
In atomic physics, Hund's rules refers to a set of rules that German physicist Friedrich Hund formulated around 1927, which are used to determine the term symbol that corresponds to the ground state of a multi-electron atom. The first rule is especially important in chemistry, where it is often referred to as, simply, Hund's Rule.
|
P.3 |
| electron configuration | [ /ˌɪˈlɛktrɑn kənˌfɪgjərˈeɪʃən/ ] | 电子排布 |
In atomic physics and quantum chemistry, the electron configuration is the distribution of electrons of an atom or molecule (or other physical structure) in atomic or molecular orbitals. For example, the electron configuration of the neon atom is 1s² 2s² 2p⁶.
|
P.3 |
| noble gas | [ /ˈnoʊbəl gæs/ ] | 惰性气体 |
The noble gases make a group of chemical elements with similar properties. Under standard conditions, they are all odorless, colorless, monatomic gases with very low chemical reactivity. The six noble gases that occur naturally are helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and the radioactive radon (Rn).
|
P.3 |
| excited state | [ /ɪkˈsaɪtɪd steɪt/ ] | 激发态 |
In quantum mechanics an excited state of a system (such as an atom, molecule or nucleus) is any quantum state of the system that has a higher energy than the ground state (that is, more energy than the absolute minimum).
|
P.3 |
| ground state | [ /graʊnd steɪt/ ] | 基态 |
The ground state of a quantum mechanical system is its lowest-energy state; the energy of the ground state is known as the zero-point energy of the system. An excited state is any state with energy greater than the ground state.
|
P.3 |
| momentum | [ /moʊˈmɛntəm/ ] | 动量 |
The quantity of motion of a moving body, measured as a product of its mass and velocity.
|
P.3 |
| the Heisenberg uncertainty principle | [ /ðə ˈhaɪzənbɜːrɡ ənˈsərtənti ˈprɪnsəpəl/ ] | 海森堡测不准原理 |
In quantum mechanics, the uncertainty principle (also known as Heisenberg's uncertainty principle) is any of a variety of mathematical inequalities asserting a fundamental limit to the precision with which certain pairs of physical properties of a particle, known as complementary variables, such as position x and momentum p, can be known.
|
P.3 |
| Rydberg equation | [ /ˈrɪdbɜːrɡ ɪkˈweɪʒən/ ] | 里德堡方程 |
The Rydberg formula is used in atomic physics to describe the wavelengths of spectral lines of many chemical elements. It was formulated by the Swedish physicist Johannes Rydberg, and presented on 5 November 1888.
|
P.3 |
| orbital | [ /ˈɔrbətəl/ ] | 轨道 |
In chemistry and quantum mechanics, an orbital is a mathematical function that describes the wavelike behavior of an electron, electron pair, or (less commonly) nucleons. An orbital may also be called an atomic orbital or electron orbital.
|
P.3 |
| Periodic Table of the Elements | [ /ˌpɪriˈɑdɪk ˈteɪbəl əv ðə ˈɛləmənts/ ] | 元素周期表 |
The periodic table is a tabular arrangement of the chemical elements, ordered by their atomic number (number of protons), electron configurations, and recurring chemical properties. This ordering shows periodic trends, such as elements with similar behavior in the same column. It also shows four rectangular blocks with some approximately similar chemical properties.
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P.4 |
| atomic symbols | [ /əˈtɑmɪk ˈsɪmbəlz/ ] | 元素符号 [注: 原PDF误作元字符号] |
Atomic symbol, sometimes called a chemical symbol, is a one to three letter code for chemical elements.
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P.4 |
| formula | [ /ˈfɔrmjələ/ ] | 方程式 |
A mathematical relationship or rule expressed in symbols.
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P.4 |
| ion | [ /aɪən/ ] | 离子 |
An atom or molecule with a net electric charge due to the loss or gain of one or more electrons.
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| isotope | [ /ˈaɪsətoʊp/ ] | 同位素 |
Isotopes are variants of a particular chemical element which differ in neutron number, although all isotopes of a given element have the same number of protons in each atom. The term isotope is formed from the Greek roots isos and topos, meaning "the same place"; thus, the meaning behind the name is that different isotopes of a single element occupy the same position on the periodic table.
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| subscript | [ /sˈʌbskrˌɪpt/ ] | 下标 |
(of a letter, figure, or symbol) Written or printed below the line.
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| atomic number | [ /əˈtɑmɪk ˈnəmbər/ ] | 原子序数 |
In chemistry and physics, the atomic number of a chemical element (also known as its proton number) is the number of protons found in the nucleus of an atom of that element, and therefore identical to the charge number of the nucleus. It is conventionally represented by the symbol Z. The atomic number uniquely identifies a chemical element.
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P.4 |
| weighted averages of the masses | [ /ˈweɪtɪd ˈævrɪʤɪz əv ðə ˈmæsɪz/ ] | 平均质量 |
To find the AVERAGE ATOMIC MASS of an atom, we take into account all of the isotopes that exist and the percentage of each type. The calculation of the average atomic mass is a WEIGHTED AVERAGE. Average atomic mass = Σ (mass of isotope × relative abundance)
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P.4 |
| main group | [ /meɪn grup/ ] | 主族 |
In chemistry and atomic physics, the main group is the group of elements whose lightest members are represented by helium, lithium, beryllium, boron, carbon, nitrogen, oxygen, fluorine, and neon as arranged in the periodic table of the elements. The main group includes the elements (except hydrogen) in groups 1 and 2 (s-block), and groups 13 to 18 (p-block).
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P.4 |
| atomic radius | [ /əˈtɑmɪk ˈreɪdiəs/ ] | 原子半径 |
The atomic radius of a chemical element is a measure of the size of its atoms, usually the mean or typical distance from the center of the nucleus to the boundary of the surrounding cloud of electrons. Since the boundary is not a well-defined physical entity, there are various non-equivalent definitions of atomic radius.
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P.4 |
| nuclear charge | [ /ˈnukliər ʧɑrʤ/ ] | 核电核力 |
The nuclear charge is the total charge of all the protons in the nucleus. It has the same value as the atomic number.
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P.4 |
| effective nuclear charge | [ /ˈifɛktɪv ˈnukliər ʧɑrʤ/ ] | 有效核电荷数 |
The effective nuclear charge is the net positive charge experienced by an electron in a multi-electron atom. The term "effective" is used because the shielding effect of negatively charged electrons prevents higher orbital electrons from experiencing the full nuclear charge of the nucleus due to the repelling effect of inner-layer electrons.
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P.4 |
| electronegativity | [ /ɪˌlɛktroʊˌnɛɡəˈtɪvəti/ ] | 电负性 |
Electronegativity, symbol χ, is a chemical property that describes the tendency of an atom or a functional group to attract electrons (or electron density) towards itself. An atom's electronegativity is affected by both its atomic number and the distance at which its valence electrons reside from the charged nucleus.
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P.5 |
| affinity | [ /əˈfɪnɪti/ ] | 亲和性 |
In chemical physics and physical chemistry, chemical affinity is the electronic property by which dissimilar chemical species are capable of forming chemical compounds.
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P.5 |
| non-metal | [ /nɑːnmˈɛtəl/ ] | 非金属 |
In chemistry, a non-metal (or non-metal) is a chemical element that mostly lacks metallic attributes. Physically, non-metals tend to have relatively low melting and boiling points, and densities, are mostly brittle if solid, and are usually poor conductors of heat and electricity; chemically, they tend to have relatively high ionization energy, electron affinity, and electronegativity values, and gain or share electrons when they react with other elements or compounds. Seventeen elements are generally classified as non-metals; most are gases (hydrogen, helium, nitrogen, oxygen, fluorine, neon, chlorine, argon, krypton, xenon and radon); one is a liquid (bromine), and a few are solids (carbon, phosphorus, sulfur, selenium, and iodine). Metalloids such as boron, silicon and germanium are sometimes counted as non-metals.
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| metal | [ /ˈmɛtəl/ ] | 金属 |
A metal (from Greek μέταλλον métallon, "mine, quarry, metal") is a material that, when freshly prepared, polished, or fractured, has a lustrous appearance, and conducts both electricity and heat relatively well. Metals are typically malleable (they can be hammered into thin sheets) or ductile (can be drawn into wires). A metal may be a pure chemical element such as gold, or an alloy of variable composition such as stainless steel, or an alloy of fixed composition, otherwise known as an intermetallic compound, such as one of the nickel aluminides, Ni3Al, NiAl, or NiAl3. Most elemental metals are denser than other elements; iron, for example, is heavier than carbon, and sulfur.
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| boiling points | [ /ˈbɔɪlɪŋ pɔɪnts/ ] | 沸点 |
The boiling point of a substance is the temperature at which the vapor pressure of the liquid equals the pressure surrounding the liquid and the liquid changes into a vapor. The boiling point of a liquid varies depending upon the surrounding environmental pressure. A liquid in a partial vacuum has a lower boiling point than when that liquid is at atmospheric pressure.
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P.5 |
| group | [ /grup/ ] | 族 |
In chemistry, a group is a vertical column in the Periodic Table. Groups may be referred to either by number or by name. For example, Group 1 is also known as the Alkali Metals.
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| valence electrons | [ /ˈveɪləns ˌɪˈlɛktrɑnz/ ] | 价电子 |
In chemistry, a valence electron is an electron that is associated with an atom, and that can participate in the formation of a chemical bond; in a single covalent bond, both atoms in the bond contribute one valence electron in order to form a shared pair.
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| third ionization energy | [ /θərd ˌaɪənəˈzeɪʃən ˈɛnərʤi/ ] | 第三电离能 |
The third ionization energy is the energy required to form 3+ cations: M 2+ (g) → M 3+ (g) + e-and so on. Ionization energies are always positive numbers, because energy must be supplied (an endothermic energy change) to separate electrons from atoms.
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P.5 |
| quantum number | [ /kˈwɑntəm ˈnəmbər/ ] | 量子数 |
Quantum numbers describe values of conserved quantities in the dynamics of a quantum system. In the case of quantum numbers of electrons, they can be defined as "the sets of numerical values which give acceptable solutions to the Schrödinger wave equation for the hydrogen atom".
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| principal quantum number | [ /ˈprɪnsəpəl kˈwɑntəm ˈnəmbər/ ] | 主量子数 |
In quantum mechanics, the principal quantum number (symbolized n) is one of four quantum numbers which are assigned to each electron in an atom to describe that electron's state. As a discrete variable, the principal quantum number is always an integer. As n increases, the number of electronic shells increases and the electron spends more time farther from the nucleus.
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P.5 |
| angular momentum quantum number | [ /ˈæŋgjələr moʊˈmɛntəm kˈwɑntəm ˈnəmbər/ ] | 角量子数 |
A quantum number for an atomic orbital that determines its orbital angular momentum and describes the shape of the orbital. Also known as the azimuthal quantum number.
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P.6 |
| sublevel | [ /sˈʌbləvəl/ ] | 亚层 |
A sublevel is an energy level defined by quantum theory. In chemistry, sublevels refer to energies associated with electrons. In physics, sublevels may also refer to energies associated with the nucleus.
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P.6 |
| magnetic quantum number | [ /mægˈnɛtɪk kˈwɑntəm ˈnəmbər/ ] | 磁量子数 |
In atomic physics, the magnetic quantum number is the third of a set of quantum numbers (the principal quantum number, the azimuthal quantum number, the magnetic quantum number, and the spin quantum number) which describe the unique quantum state of an electron and is designated by the letter m. The magnetic quantum number denotes the energy levels available within a subshell.
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P.6 |
| spin quantum number | [ /spɪn kˈwɑntəm ˈnəmbər/ ] | 自旋量子数 |
In atomic physics, the spin quantum number is a quantum number that parameterizes the intrinsic angular momentum (or spin angular momentum, or simply spin) of a given particle.
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P.6 |
| physical properties | [ /ˈfɪzɪkəl ˈprɑpərtiz/ ] | 物理性质 |
A physical property is any property that is measurable, whose value describes a state of a physical system. The changes in the physical properties of a system can be used to describe its transformations or evolutions between its momentary states. Physical properties are often referred to as observables. They are not modal properties. Quantifiable physical property is called physical quantity.
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| energy level | [ /ˈɛnərʤi ˈlɛvəl/ ] | 能级 |
A quantum mechanical system or particle that is bound—that is, confined spatially—can only take on certain discrete values of energy. This contrasts with classical particles, which can have any energy. These discrete values are called energy levels.
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P.6 |
| Democritus | [ /dəmˈɑːkrətəs/ ] | 德谟克利特 |
(c.460–c.370 bc) Greek philosopher. He developed the atomic theory originated by his teacher, Leucippus, which explained natural phenomena in terms of the arrangement and rearrangement of atoms moving in a void.
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| atom | [ /ˈætəm/ ] | 原子 |
An atom is the smallest constituent unit of ordinary matter that has the properties of a chemical element. Every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. Atoms are extremely small; typical sizes are around 100 picometers. Atoms are small enough that attempting to predict their behavior using classical physics – as if they were billiard balls, for example – gives noticeably incorrect predictions due to quantum effects.
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P.6 |
| atomic theory | [ /əˈtɑmɪk ˈθɪri/ ] | 原子理论 |
In chemistry and physics, atomic theory is a scientific theory of the nature of matter, which states that matter is composed of discrete units called atoms. It began as a philosophical concept in ancient Greece and entered the scientific mainstream in the early 19th century when discoveries in the field of chemistry showed that matter did indeed behave as if it were made up of atoms.
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P.6 |
| plum pudding model | [ /pləm ˈpʊdɪŋ ˈmɑdəl/ ] | 枣糕模型 |
The plum pudding model was a model of the atom that incorporated the recently discovered electron, and was proposed by J. J. Thomson in 1904. Thomson had discovered the electron in 1897.
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P.6 |
| Solar System model | [ /ˈsoʊlər ˈsɪstəm ˈmɑdəl/ ] | 原子太阳系模型 |
An analogy often used in chemistry to describe the atom as “the solar system”, but not everyone agrees on its helpfulness.
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P.6 |
| chemical reactions | [ /ˈkɛmɪkəl riˈækʃənz/ ] | 化学反应 |
A chemical reaction is a process that leads to the transformation of one set of chemical substances to another. Classically, chemical reactions encompass changes that only involve the positions of electrons in the forming and breaking of chemical bonds between atoms, with no change to the nuclei (no change to the elements present), and can often be described by a chemical equation.
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P.6 |
| John Dalton | [ /ʤɑn ˈdɔːltən/ ] | 约翰·道尔顿 |
John Dalton FRS (/ˈdɔːltən/; 6 September 1766 – 27 July 1844) was an English chemist, physicist, and meteorologist. He is best known for introducing the atomic theory into chemistry, and for his research into color blindness, sometimes referred to as Daltonism in his honor.
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P.6 |
| law of multiple proportions | [ /lɔ əv ˈməltəpəl prəˈpɔrʃənz/ ] | 倍比定律 |
Law of multiple proportions, statement that when two elements combine with each other to form more than one compound, the weights of one element that combine with a fixed weight of the other are in a ratio of small whole numbers.
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P.7 |
| J. J. Thomson | [ /ʤeɪ ʤeɪ ˈtɑmsən/ ] | 约瑟夫·汤姆孙 |
Sir Joseph John Thomson OM PRS (18 December 1856 – 30 August 1940) was an English physicist and Nobel Laureate in Physics, credited with the discovery and identification of the electron; and with the discovery of the first subatomic particle.
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P.7 |
| Henri Becquerel | [ /ˌɔˈri bˈɛkwˌɛrəl/ ] | 法国物理学家贝克勒尔 |
Antoine Henri Becquerel was a French physicist, Nobel laureate, and the first person to discover evidence of radioactivity. For work in this field he, along with Marie Skłodowska-Curie and Pierre Curie, received the 1903 Nobel Prize in Physics. The SI unit for radioactivity, the becquerel, is named after him.
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P.7 |
| Marie Curie | [ /mərˈi ˈkjʊri/ ] | 居里夫人 |
Marie Skłodowska Curie (/ˈkjʊəri/;[3] French: [kyʁi]; Polish: [kʲiˈri]; born Maria Salomea Skłodowska;7 November 1867 – 4 July 1934) was a Polish and naturalized-French physicist and chemist who conducted pioneering research on radioactivity. She was the first woman to win a Nobel Prize, the first person and only woman to win twice, the only person to win a Nobel Prize in two different sciences, and was part of the Curie family legacy of five Nobel Prizes. She was also the first woman to become a professor at the University of Paris, and in 1995 became the first woman to be entombed on her own merits in the Panthéon in Paris.
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P.7 |
| hydrogen spectrum | [ /ˈhaɪdrəʤən ˈspɛktrəm/ ] | 氢原子光谱 |
The emission spectrum of atomic hydrogen is divided into a number of spectral series, with wavelengths given by the Rydberg formula. These observed spectral lines are due to the electron making transitions between two energy levels in the atom. The classification of the series by the Rydberg formula was important in the development of quantum mechanics.
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| The Wave-Mechanical Model | [ /ðə wˌeɪvəmˈɛkʃənəkəl ˈmɑdəl/ ] | 波动力学模型 |
The wave mechanical model is used to predict the behavior of every electron within an atom. The predictions that are obtained when using the wave mechanical model ensure that the findings are as accurate as possible.
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| cathode ray | [ /ˈkæˌθoʊd reɪ/ ] | 阴极射线 [注: 原PDF误作阴极] |
Cathode rays (also called an electron beam or e-beam) are streams of electrons observed in vacuum tubes.
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| Robert Millikan | [ /ˈrɑbərt ˈmɪləkən/ ] | 物理学家密里根 |
Robert Andrews Millikan (March 22, 1868 – December 19, 1953) was an American experimental physicist honored with the Nobel Prize for Physics in 1923 for the measurement of the elementary electronic charge and for his work on the photoelectric effect. Millikan graduated from Oberlin College in 1891 and obtained his doctorate at Columbia University in 1895. In 1896 he became an assistant at the University of Chicago, where he became a full professor in 1910.
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P.7 |
| nucleus | [ /ˈnukliəs/ ] | 原子核 |
The positively charged central core of an atom, consisting of protons and neutrons and containing nearly all its mass.
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| Chadwick Sir James, | [ /ˈʧædwɪk sər ʤeɪmz/ ] | 查德威克（姓氏；1891-1974，英国物理学家，中子的发现者，曾获1935 年诺贝尔物理学奖） |
Sir James Chadwick, CH, FRS (20 October 1891 – 24 July 1974) was a British physicist who was awarded the 1935 Nobel Prize in Physics for his discovery of the neutron in 1932. In 1941, he wrote the final draft of the MAUD Report, which inspired the U.S. government to begin serious atomic bomb research efforts. He was the head of the British team that worked on the Manhattan Project during the Second World War. He was knighted in Britain in 1945 for his achievements in physics.
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| Bohr Model of the Atom | [ /bɔr ˈmɑdəl əv ðə ˈætəm/ ] | 波尔原子模型 |
In atomic physics, the Rutherford–Bohr model or Bohr model, introduced by Niels Bohr in 1913, depicts the atom as a small, positively charged nucleus surrounded by electrons that travel in circular orbits around the nucleus—similar in structure to the solar system, but with attraction provided by electrostatic forces rather than gravity.
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| subatomic particle | [ /ˌsəbəˈtɑmɪk ˈpɑrtɪkəl/ ] | 亚原子粒子 |
In the physical sciences, subatomic particles are particles much smaller than atoms. There are two types of subatomic particles: elementary particles, which according to current theories are not made of other particles; and composite particles. Particle physics and nuclear physics study these particles and how they interact.
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P.7 |
| mass spectrometer | [ /mæs spɛkˈtrɑmətər/ ] | 质谱 |
Mass spectrometry (MS) is an analytical technique that ionizes chemical species and sorts the ions based on their mass-to-charge ratio.
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| negatively charged | [ /ˈnɛgətɪvli ʧɑrʤd/ ] | 负电 |
A negatively charged atom is called an anion. An anion forms when an atom gains electrons from another atom. Atoms are generally neutral, but they take on a charge when they gain or lose electrons.
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P.8 |
| magnet | [ /ˈmægnət/ ] | 磁石 |
A magnet is a material or object that produces a magnetic field. This magnetic field is invisible but is responsible for the most notable property of a magnet: a force that pulls on other ferromagnetic materials, such as iron, and attracts or repels other magnets.
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P.8 |
| relative isotopic abundances | [ /ˈrɛlətɪv ˌaɪsəˈtɑːpɪk əbˈʌndənsɪz/ ] | 同位素丰度 |
The relative atomic mass is the weighted average of the isotopic masses. Example: Chlorine has two isotopes 35Cl and 37Cl, with relative abundance of 75% and 25% respectively. This means that in any naturally occurring sample of chlorine 75% of the atoms are Cl-35 atoms and 25% of the atoms are chlorine-37 atoms.
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P.8 |
| photon | [ /ˈfoʊˌtɑn/ ] | 光子 |
A photon is an elementary particle, the quantum of all forms of electromagnetic radiation, including light. It is the force carrier for the electromagnetic force, even when static via virtual photons. The photon has zero rest mass and as a result, the interactions of this force with matter at long distance are observable at the microscopic and at the macroscopic level.
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| frequency | [ /ˈfrikwənsi/ ] | 频率 |
Frequency is the number of times a point on a wave passes a fixed reference point in one second. The SI unit for frequency is the Hertz (Hz). Also Known As: cycles per second. Article. Chemistry. These Are the Base Units of the Metric System The metric system or SI is based on seven base units.
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| electromagnetic | [ /ˌɪˌlɛktroʊmægˈnɛtɪk/ ] | 电磁的 adj. |
Of or exhibiting electromagnetism.
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P.8 |
| Planck’s equation | [ /plæŋk ɛs ɪkˈweɪʒən/ ] | 普朗克方程 |
Planck's law describes the spectral density of electromagnetic radiation emitted by a black body in thermal equilibrium at a given temperature T. The law is named after Max Planck, who proposed it in 1900. It is a pioneering result of modern physics and quantum theory.
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| ionization | [ /ˌaɪənəˈzeɪʃən/ ] | 电离化 |
Ionization or ionisation, is the process by which an atom or a molecule acquires a negative or positive charge by gaining or losing electrons to form ions, often in conjunction with other chemical changes.
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| wave-particle duality | [ /weɪv ˈpɑːrtɪkəl duˈæləti/ ] | 波粒二象性 [注: 原PDF误作波粒二线性] |
Wave–particle duality is the concept that every elementary particle or quantic entity may be partly described in terms not only of particles, but also of waves. It expresses the inability of the classical concepts "particle" or "wave" to fully describe the behavior of quantum-scale objects.
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| diffraction | [ /dɪˈfrækʃən/ ] | 衍射 |
The process by which a beam of light or other system of waves is spread out as a result of passing through a narrow aperture or across an edge, typically accompanied by interference between the wave forms produced.
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P.8 |
| absorbance | [ /ˈæbsərbˌæns/ ] | 吸收率 |
In chemistry, absorbance or decadic absorbance is the common logarithm of the ratio of incident to transmitted radiant power through a material, and spectral absorbance or spectral decadic absorbance is the common logarithm of the ratio of incident to transmitted spectral radiant power through a material.
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| solute | [ /sˈoʊluːt/ ] | 溶质 |
In chemistry, a solution is a special type of homogeneous mixture composed of two or more substances. The term aqueous solution is when one of the solvents is water. In such a mixture, a solute is a substance dissolved in another substance, known as a solvent. The mixing process of a solution happens at a scale where the effects of chemical polarity are involved, resulting in interactions that are specific to solvation.
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| solution | [ /səˈluʃən/ ] | 溶液 |
In chemistry, a solution is a special type of homogeneous mixture composed of two or more substances. The term aqueous solution is when one of the solvents is water.
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P.8 |
| Beer’s law | [ /bɪr ɛs lɔ/ ] | 比尔定律（比尔-朗伯定律）[注: 原PDF误作波尔定律] |
Beer’s law, also called Lambert-Beer law or Beer-Lambert law, states that the concentration of an analyte is directly proportional to the amount of light absorbed.
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P.9 |
| ultraviolet | [ /ˌəltrəˈvaɪəlɪt/ ] | 紫外的 |
Ultraviolet is electromagnetic radiation with a wavelength from 10 nm to 400 nm, shorter than that of visible light but longer than X-rays. UV radiation is present in sunlight constituting about 10% of the total light output of the Sun. It is also produced by electric arcs and specialized lights, such as mercury-vapor lamps, tanning lamps, and black lights.
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| X-ray | [ /ˈɛksˌreɪ/ ] | X 射线 |
X-radiation (composed of X-rays) is a form of electromagnetic radiation. Most X-rays have a wavelength ranging from 0.01 to 10 nanometers, corresponding to frequencies in the range 30 petahertz to 30 exahertz and energies in the range 100 eV to 100 keV. X-ray wavelengths are shorter than those of UV rays and typically longer than those of gamma rays.
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| infrared | [ /ˌɪnfrərˈɛd/ ] | 红外的 |
(Of electromagnetic radiation) Having a wavelength just greater than that of the red end of the visible light spectrum but less than that of microwaves. Infrared radiation has a wavelength from about 800 nm to 1 mm, and is emitted particularly by heated objects.
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P.9 |
| reactant | [ /riːˈæktənt/ ] | 反应物 |
A substance that takes part in and undergoes change during a reaction.
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| product | [ /ˈprɑdəkt/ ] | 产物 |
Product (chemistry) Products are the species formed from chemical reactions. During a chemical reaction reactants are transformed into products after passing through a high energy transition state.
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| sodium hydroxide | [ /ˈsoʊdiəm haɪˈdrɑksaɪd/ ] | 氢氧化钠 |
Sodium hydroxide, also known as lye and caustic soda, is an inorganic compound with the formula NaOH. It is a white solid ionic compound consisting of sodium cations Na⁺ and hydroxide anions OH⁻.
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P.9 |
| molar ratio | [ /mˈoʊlər ˈreɪʃiˌoʊ/ ] | 摩尔比例 |
Molar ratio is the proportion of one substance to another in a given chemical reaction. It is the ratio of their coefficients in the chemical equation. For example, in the synthesis of water, the mole ratio of Hydrogen (H2) to Oxygen (O2) is 1:2.
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| Law of Conservation of Mass | [ /lɔ əv ˌkɑnsərˈveɪʃən əv mæs/ ] | 质量守恒定律 |
The law of conservation of mass or principle of mass conservation states that for any system closed to all transfers of matter and energy, the mass of the system must remain constant over time, as system mass cannot change quantity if it is not added or removed. Hence, the quantity of mass is "conserved" over time.
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| coefficient | [ /ˌkoʊəˈfɪʃənt/ ] | 系数 |
Coefficients are the numbers placed before the reactants in a chemical equation so that the number of atoms in the products on the right side of the equation are equal to the number of atoms in the reactants on the left side.
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| gravimetric analysis | [ /ˌgrævəˈmɛtrɪk æˈnælɪsɪs/ ] | 重量分析 |
Gravimetric analysis describes a set of methods in analytical chemistry for the quantitative determination of an analyte based on the mass of a solid. For instance, the measurement of solids suspended in a water sample: A known volume of water is filtered, and the collected solids are weighed.
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| sample | [ /ˈsæmpəl/ ] | 样本 |
A small part or quantity intended to show what the whole is like.
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| hydrate | [ /ˈhaɪˌdreɪt/ ] | 水合物 |
In chemistry, a hydrate is a substance that contains water or its constituent elements. The chemical state of the water varies widely between different classes of hydrates, some of which were so labelled before their chemical structure was understood.
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| anion | [ /ˈænaɪən/ ] | 阴离子 |
A negatively charged ion.
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| ammonia | [ /əˈmoʊnjə/ ] | 氨 |
Ammonia is a compound of nitrogen and hydrogen with the formula NH3. The simplest pnictogen hydride, ammonia, is a colorless gas with a characteristic pungent smell. It is a common nitrogenous waste, particularly among aquatic organisms, and it contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to food and fertilizers.
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P.9 |
| titration | [ /taɪˈtreɪʃən/ ] | 滴定 |
Titration, also known as titrimetry, is a common laboratory method of quantitative chemical analysis that is used to determine the concentration of an identified analyte. Since volume measurements play a key role in titration, it is also known as volumetric analysis. A reagent, called the titrant or titrator, is prepared as a standard solution. A known concentration and volume of titrant reacts with a solution of analyte or titrand to determine concentration. The volume of titrant reacted is called titration volume.
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| crystal | [ /ˈkrɪstəl/ ] | 晶体 |
A crystal or crystalline solid is a solid material whose constituents, such as atoms, molecules or ions, are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions. In addition, macroscopic single crystals are usually identifiable by their geometrical shape, consisting of flat faces with specific, characteristic orientations.
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| equivalent | [ /ɪkˈwɪvələnt/ ] | 等量 adj. |
Equal in value, amount, function, and meaning.
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| spectrophotometry | [ /spˌɛkstˌɑːrθətˈɑːmɪtiː/ ] | 分光光度法 |
In chemistry, spectrophotometry is the quantitative measurement of the reflection or transmission properties of a material as a function of wavelength. It is more specific than the general term electromagnetic spectroscopy in that spectrophotometry deals with visible light, near-ultraviolet, and near-infrared, but does not cover time-resolved spectroscopic techniques.
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| electrochemical series | [ /ˌəˌlɛktroʊˈkɛmɪkəl ˈsɪriz/ ] | 元素电化序 |
Electrochemical series is a series of chemical elements arranged in order of their standard electrode potentials.
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| pH indicator | [ /ˈpiˈeɪʧ ˈɪndəˌkeɪtər/ ] | 酸碱指示剂 |
A pH indicator is a halochromic chemical compound added in small amounts to a solution so the pH (acidity or basicity) of the solution can be determined visually. Hence, a pH indicator is a chemical detector for hydronium ions (H 3 O +) or hydrogen ions (H +) in the Arrhenius model.
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| common-ion effect | [ /kˈɑːmənjən ˈifɛkt/ ] | 同离子效应 |
The common ion effect is responsible for the reduction in the solubility of an ionic precipitate when a soluble compound containing one of the ions of the precipitate is added to the solution in equilibrium with the precipitate.
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| burette | [ /bjʊˈrɛt/ ] | 滴定管 |
A burette (also burette) is a device used in analytical chemistry for the dispensing of variable, measured amounts of a chemical solution. A volumetric burette delivers measured volumes of liquid. Piston burettes are similar to syringes, but with precision bore and plunger. Piston burettes may be manually operated or may be motorized. A weight burette delivers measured weights of liquid.
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| buffering effect | [ /ˈbəfərɪŋ ˈifɛkt/ ] | 缓冲效果 |
A buffering effect is a process in which a psychosocial resource reduces the impact of life stress on psycho-logical well-being. Having such a resource contributes to adjustment because persons are less affected by negative life events.
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| neutral | [ /ˈnutrəl/ ] | 中性的 adj. |
A neutral pH level is a value of seven on the pH scale. This number lies at the center of the scale and is the value that is associated with pure water. A pH level below or above seven indicates that the liquid is either an acid or a base.
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| conjugate | [ /ˌkɑnʤəˈgeɪt/ ] | 共轭 |
In chemistry, a conjugated system is a system of connected p-orbitals with delocalized electrons in molecules which are conventionally represented as having alternating single and multiple bonds, which in general may lower the overall energy of the molecule and increase stability.
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| limiting reagent | [ /ˈlɪmətɪŋ ˈriʤənt/ ] | 限量反应物 |
The limiting reagent (or limiting reactant) in a chemical reaction is the substance that is totally consumed when the chemical reaction is complete. The amount of product formed is limited by this reagent, since the reaction cannot continue without it.
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| polyprotic acid | [ /pˌɑːlɪprˈoʊtɪk ˈæsəd/ ] | 多元酸 |
A polyprotic acid is an acid which contains more than one ionizable hydrogen (H+) per acid molecule. The acid ionizes one step at a time in an aqueous solution, with a separate ionization constant for each step. The initial dissociation is the primary source of H+, so it is the main factor in determining the pH of the solution.
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| vacuum | [ /ˈvækjum/ ] | 真空 |
Vacuum is a volume that encloses little or no matter. A partial vacuum is a vacuum with low amounts of matter enclosed. A total or absolute vacuum has no matter enclosed.
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P.11 |
| filtration | [ /fɪlˈtreɪʃən/ ] | 过滤 |
Filtration is any of various mechanical, physical or biological operations that separate solids from fluids by adding a medium through which only the fluid can pass. The fluid that passes through is called the filtrate. In physical filters oversize solids in the fluid are retained and in biological filters particulates are trapped and ingested and metabolites are retained and removed.
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| bond | [ /bɑnd/ ] | 键 |
A chemical bond is any of several forces or mechanisms, especially the ionic bond, covalent bond, and metallic bond, by which atoms or ions are bound in a molecule or crystal. There are two types of chemical bonds mainly, these are the ionic and covalent bonds.
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| melt | [ /mɛlt/ ] | 熔化 v. |
In physics and chemistry, melting is the process of converting a solid substance to its liquid form, typically by heating the substance to a temperature called its melting point.
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| amorphous | [ /əˈmɔrfəs/ ] | 无定型的 adj. |
In physics and chemistry, amorphous is a term used to describe a solid which does not exhibit crystalline structure. While there may be local ordering of the atoms or molecules in an amorphous solid, no long-term ordering is present.
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| network | [ /ˈnɛtˌwərk/ ] | 网络的 |
A network solid or covalent network solid is a chemical compound (or element) in which the atoms are bonded by covalent bonds in a continuous network extending throughout the material. In a network solid there are no individual molecules, and the entire crystal or amorphous solid may be considered a macromolecule.
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| polymer | [ /ˈpɑləmər/ ] | 聚合物 |
A polymer is a large molecule, or macromolecule, composed of many repeated subunits. Due to their broad range of properties, both synthetic and natural polymers play essential and ubiquitous roles in everyday life. Polymers range from familiar synthetic plastics such as polystyrene to natural biopolymers such as DNA and proteins that are fundamental to biological structure and function.
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| surface tension | [ /ˈsərfəs ˈtɛnʃən/ ] | 表面张力 |
Surface tension is the elastic tendency of a fluid surface which makes it acquire the least surface area possible. Surface tension allows insects (e.g. water striders), usually denser than water, to float and stride on a water surface.
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| intermolecular | [ /ˌɪntərməˈlɛkjələr/ ] | 分子之间的 adj. |
Existing or taking place between molecules.
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| viscosity | [ /vɪˈskɑsəti/ ] | 粘度 |
The viscosity of a fluid is a measure of its resistance to gradual deformation by shear stress or tensile stress. For liquids, it corresponds to the informal concept of "thickness". For example, honey has a much higher viscosity than water.
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| phase | [ /feɪz/ ] | 相 |
A distinct and homogeneous form of matter (i.e. a particular solid, liquid, or gas) separated by its surface from other forms.
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| a heating curve | [ /ə ˈhitɪŋ kərv/ ] | 加热曲线 |
A heating curve shows the relationship of the temperature and heat input of a system as that system is heated over time.
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| vapor | [ /ˈveɪpər/ ] | 蒸汽 |
In physics a vapor or vapour is a substance in the gas phase at a temperature lower than its critical temperature, which means that the vapor can be condensed to a liquid by increasing the pressure on it without reducing the temperature. A vapor is different from an aerosol. An aerosol is a suspension of tiny particles of liquid, solid, or both within a gas.
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| metastable state | [ /mˈɛtəstəbəl steɪt/ ] | 亚稳定状态 |
Metastability denotes the phenomenon when a system spends an extended time in a configuration other than the system's state of least energy. During a metastable state of finite lifetime all state-describing parameters reach and hold stationary values.
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| macroscopic | [ /mˌærkoʊskˈɑːpɪk/ ] | 宏观的 adj. |
Visible to the naked eye; not microscopic.
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| Kinetic Molecular Theory | [ /kɪˈnɛtɪk məˈlɛkjələr ˈθɪri/ ] | 分子动能论 |
The kinetic molecular theory is a collection of several rules that describe the behavior of gases. The nature of gas molecules was examined by scientists, such as Robert Boyle and Jacques Charles, who outlined their observations in several laws that eventually became the Kinetic Molecular Theory.
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| random | [ /ˈrændəm/ ] | 随机的 adj. |
Proceeding, made, or occurring without definite aim, reason, or pattern.
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| pressure | [ /ˈprɛʃər/ ] | 压强 |
Continuous physical force exerted on or against an object by something in contact with it.
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| proportional | [ /prəˈpɔrʃənəl/ ] | 按照比例的 adj. |
Corresponding in size or amount to something else.
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| elastic collision | [ /ɪˈlæstɪk kəˈlɪʒən/ ] | 弹性碰撞 |
Elastic Collision is the collision in which colliding objects rebound without lasting deformation or heat generation. Inelastic collision is a collision in which the colliding objects become distorted and generate heat during collision and possibly stick together.
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| ideal gas | [ /aɪˈdil gæs/ ] | 理想气体 |
An ideal gas is a theoretical gas composed of many randomly moving point particles that do not interact except when they collide elastically. The ideal gas concept is useful because it obeys the ideal gas law, a simplified equation of state, and is amenable to analysis under statistical mechanics. One mole of an ideal gas has a volume of 22.7 L at STP as defined by IUPAC.
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| non-polar | [ /nˈɑːnpˌɔːlər/ ] | 非极性 |
A non-polar solvent is one with molecules that have roughly the same electrical charge on all sides; in other words, it has low static permittivity. Non-polar solvents are typically hydrocarbons, such as pentane and hexane. Each atom on the periodic table has an electronegativity value that describes its ability to bond to other atoms.
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| polar | [ /ˈpoʊlər/ ] | 极性 |
Polar in chemistry, also known as a polar covalent bond, happens when 2 or more non-metals create a bond. Polar bonds are usually liquids or solids and are soluble. For example, water (H2O) is polar covalent. It is made up of Hydrogen and Oxygen, with hydrogen having a partial positive and oxygen with a partial negative.
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| gas law | [ /gæs lɔ/ ] | 气体定理 |
Laws that relate the pressure, volume, and temperature of a gas.
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| Boyle’s law | [ /bɔɪl ɛs lɔ/ ] | 波义尔定律 |
Boyle's law (sometimes referred to as the Boyle–Mariotte law, or Mariotte's law) is an experimental gas law that describes how the pressure of a gas tends to increase as the volume of a gas decreases.
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| Charles’s law | [ /ˈʧɑrəlz ɛs lɔ/ ] | 查理定理 |
Charles' law (also known as the law of volumes) is an experimental gas law that describes how gases tend to expand when heated.
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| Gay-Lussac’s Law | [ /ɡˈeɪləskə ɛs lɔ/ ] | 盖-吕萨克 原理 |
Gay-Lussac’s law is a gas law that states that the pressure of a given mass of gas varies directly with the absolute temperature of the gas when the volume is kept constant.
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| Combined Gas Law | [ /kəmˈbaɪnd gæs lɔ/ ] | 气体定律 |
The combined gas law combines the three gas laws: Boyle's Law, Charles' Law, and Gay-Lussac's Law. It states that the ratio of the product of pressure and volume and the absolute temperature of a gas is equal to a constant. When Avogadro's law is added to the combined gas law, the ideal gas law results. Unlike the named gas laws, the combined gas law doesn't have an official discoverer. It is simply a combination of the other gas laws that works when everything except temperature, pressure, and volume are held constant.
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| Avogadro’s Law | [ /ˌævəˈɡɑːdroʊ ɛs lɔ/ ] | 阿伏加德罗定律 [注: 原PDF误作阿伏伽德罗常数] |
A modern statement of Avogadro's law is: Avogadro's law states that, "equal volumes of all gases, at the same temperature and pressure, have the same number of molecules". For a given mass of an ideal gas, the volume and amount (moles) of the gas are directly proportional if the temperature and pressure are constant.
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| Ideal Gas Equation | [ /aɪˈdil gæs ɪkˈweɪʒən/ ] | 理想气体方程 |
The ideal gas law is the equation of state of a hypothetical ideal gas. It is a good approximation to the behavior of many gases under many conditions, although it has several limitations.
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| ideal gas constant | [ /aɪˈdil gæs ˈkɑnstənt/ ] | 理想气体常数 |
The ideal gas constant is also known as the universal gas constant or the molar gas constant or simply the gas constant, denoted as R. The dimension of the gas constant is expressed in energy per unit mole per unit temperature. The value of the gas constant in SI unit is 8.314 J mol−1 K−1. The gas constant has the same unit as of entropy and molar heat capacity.
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| Kelvin temperature | [ /ˈkɛlvɪn ˈtɛmpərəʧər/ ] | 开尔文温度 |
The kelvin is a unit of measure for temperature based upon an absolute scale. It is one of the seven base units in the International System of Units (SI) and is assigned the unit symbol K. The Kelvin scale is an absolute, thermodynamic temperature scale using as its null point absolute zero, the temperature at which all thermal motion ceases in the classical description of thermodynamics.
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| Dalton’s Law of Partial Pressures | [ /ˈdɔːltən ɛs lɔ əv ˈpɑrʃəl ˈprɛʃərz/ ] | 道尔顿分压定律 |
In chemistry and physics, Dalton's law (also called Dalton's law of partial pressures) states that in a mixture of non-reacting gases, the total pressure exerted is equal to the sum of the partial pressures of the individual gases.
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| Non-Ideal Gases | [ /nˈɑːndˈaɪlə ˈgæsɪz/ ] | 非理想气体 |
An ideal gas is a theoretical idea – a gas in which there are no attractive forces between the molecules, and in which the molecules take up no space. But both of these assumptions are incorrect in the real world. All gases in the real world have molecules with diameters and which interact with each other, so there's always a bit of error involved in using any form of the Ideal Gas Law.
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| van der Waals equation | [ /væn dər wˈɔːlz ɪkˈweɪʒən/ ] | 范德华方程 |
The van der Waals equation (or van der Waals equation of state) is an equation relating the density of gases and liquids (fluids) to the pressure (p), volume (V), and temperature (T) conditions (i.e., it is a thermodynamic equation of state).
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| carbon monoxide | [ /ˈkɑrbən məˈnɑksaɪd/ ] | 一氧化碳 |
Carbon monoxide (CO) is a colorless, odorless, and tasteless gas that is slightly less dense than air.
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| effuse | [ /ɪfjˈuːz/ ] | 泻流 v. [注: 区分于扩散 diffuse] |
Give off (a liquid, light, smell, or quality).
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| graduated cylinder | [ /ˈgræʤəˌweɪtɪd ˈsɪlɪndər/ ] | 量筒 |
A graduated cylinder, measuring cylinder or mixing cylinder is a common piece of laboratory equipment used to measure the volume of a liquid. It has a narrow cylindrical shape. Each marked line on the graduated cylinder represents the amount of liquid that has been measured.
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| absolute temperature | [ /ˈæbsəˌlut ˈtɛmpərəʧər/ ] | 绝对温度 |
A temperature measured from absolute zero in kelvins.
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| Graham’s law of effusion | [ /græm ɛs lɔ əv ɪfjˈuːʒən/ ] | 格拉汉姆气体扩散定律 |
Graham's law of effusion (also called Graham's law of diffusion) was formulated by Scottish physical chemist Thomas Graham in 1848. Graham found experimentally that the rate of effusion of a gas is inversely proportional to the square root of the mass of its particles.
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| molar mass | [ /mˈoʊlər mæs/ ] | 摩尔质量 |
In chemistry, the molar mass M is a physical property defined as the mass of a given substance (chemical element or chemical compound) divided by its amount of substance. The base SI unit for molar mass is kg/mol. However, for historical reasons, molar masses are almost always expressed in g/mol.
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| homogeneous | [ /ˌhoʊməˈʤiniəs/ ] | 同质的 adj. |
A Homogeneous mixture is a solid, liquid or gaseous mixture that has the same proportions of its components throughout a given sample.
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| colloid | [ /ˈkɑlɔɪd/ ] | 胶体 |
A homogeneous noncrystalline substance consisting of large molecules or ultramicroscopic particles of one substance dispersed through a second substance. Colloids include gels, sols, and emulsions; the particles do not settle, and cannot be separated out by ordinary filtering or centrifuging like those in a suspension.
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| heterogeneous | [ /ˌhɛtərəˈʤinjəs/ ] | 异质的 adj. |
In chemistry, a heterogeneous mixture consists of either or both of a) multiple states of matter or b) hydrophilic and hydrophobic substances in one mixture; an example of the latter would be a mixture of water, octane, and silicone grease.
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| micrometer | [ /maɪˈkrɑmətər/ ] | 千分尺 |
A micrometer, sometimes known as a micrometer screw gauge, is a device incorporating a calibrated screw widely used for precise measurement of components in mechanical engineering and machining as well as most mechanical trades, along with other metrological instruments such as dial, vernier, and digital calipers.
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| chromatography | [ /kroʊməˈtɑgrəfi/ ] | 层析 |
Chromatography is the collective term for a set of laboratory techniques for the separation of mixtures. The mixture is dissolved in a fluid called the mobile phase, which carries it through a structure holding another material called the stationary phase. The various constituents of the mixture travel at different speeds, causing them to separate.
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| intermolecular force | [ /ˌɪntərməˈlɛkjələr fɔrs/ ] | 分子间作用力 |
Intermolecular forces are the forces which mediate interaction between molecules, including forces of attraction or repulsion which act between molecules and other types of neighboring particles, e.g., atoms or ions. Intermolecular forces are weak relative to intramolecular forces – the forces which hold a molecule together. For example, the covalent bond, involving sharing electron pairs between atoms, is much stronger than the forces present between neighboring molecules.
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| component | [ /kəmˈpoʊnənt/ ] | 组成部分 |
A part or element of a larger whole.
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| distillation | [ /ˌdɪstəˈleɪʃən/ ] | 蒸馏 |
Distillation is a process of separating the component substances from a liquid mixture by selective evaporation and condensation. Distillation may result in essentially complete separation (nearly pure components), or it may be a partial separation that increases the concentration of selected components of the mixture.
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| condenser | [ /kənˈdɛnsər/ ] | 冷凝器 |
An apparatus or container for condensing vapor.
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| permanent dipole | [ /ˈpərmɑˌnɛnt ˈdaɪˌpoʊl/ ] | 永久偶极矩 |
A permanent dipole is created in a molecule when there is an electronegative atom, such as oxygen, nitrogen or a halogen. The permanent dipole consists of regions of partial positive charge and regions of partial negative charge within the same molecule.
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| hydrogen bonding | [ /ˈhaɪdrəʤən ˈbɑndɪŋ/ ] | 氢键 |
A hydrogen bond is the electrostatic attraction between polar groups that occurs when a hydrogen (H) atom bound to a highly electronegative atom such as nitrogen (N), oxygen (O) or fluorine (F) experiences attraction to some other nearby highly electronegative atom.
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| melting point | [ /ˈmɛltɪŋ pɔɪnt/ ] | 熔点 |
Melting point, temperature at which the solid and liquid forms of a pure substance can exist in equilibrium. As heat is applied to a solid, its temperature will increase until the melting point is reached. More heat then will convert the solid into a liquid with no temperature change.
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| sublimation | [ /sˌʌblɪmˈeɪʃən/ ] | 升华 |
Sublimation is the transition of a substance directly from the solid to the gas phase, without passing through the intermediate liquid phase. Sublimation is an endothermic process that occurs at temperatures and pressures below a substance's triple point in its phase diagram, which corresponds to the lowest pressure at which the substance can exist as a liquid. The reverse process of sublimation is deposition or desublimation, in which a substance passes directly from a gas to a solid phase.
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| dipole | [ /ˈdaɪˌpoʊl/ ] | 偶极 |
A dipole is a separation of electrical charges. In chemistry, a dipole refers to the separation of charges within a molecule between two covalently bonded atoms.
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| London dispersion force | [ /ˈləndən dɪˈspərʒən fɔrs/ ] | 伦敦色散力 |
London dispersion forces (LDF, also known as dispersion forces, London forces, instantaneous dipole–induced dipole forces, or loosely van der Waals forces) are a type of force acting between atoms and molecules. They are part of the van der Waals forces. The LDF is named after the German-American physicist Fritz London.
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| temporary dipole | [ /ˈtɛmpərˌɛri ˈdaɪˌpoʊl/ ] | 瞬时偶极 |
Temporary dipoles are when the electron clouds' density around a nucleus shifts in density, forming temporary dipoles. This is to say that the concentration of electrons are more concentrated in one part of a molecule than anywhere else.
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| straight-chain | [ /strˈeɪtʃˌeɪn/ ] | 直链的 |
A chain of atoms in a molecule, usually carbon atoms, that is neither branched nor formed into a ring.
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| electronegative | [ /ɪlˌɛktroʊˈæntɪɡət/ ] | 负电性的 adj。 |
(of an element) Tending to acquire electrons and form negative ions in chemical reactions.
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| three-dimensional | [ /θˌrizdɪˈmɛnʃənəl/ ] | 3D 立体的 |
Having or appearing to have length, breadth, and depth.
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| capillary action | [ /ˈkæpəˌlɛri ˈækʃən/ ] | 毛细作用 |
Capillary action (sometimes capillarity, capillary motion, or wicking) is the ability of a liquid to flow in narrow spaces without the assistance of, or even in opposition to, external forces like gravity.
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| miscible | [ /ˈmɪsəbəl/ ] | 互溶的 adj. |
(of liquids) forming a homogeneous mixture when added together.
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| soluble | [ /ˈsɑljəbəl/ ] | 溶解的 adj. |
(of a substance) Able to be dissolved, especially in water.
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| deviations | [ /diviˈeɪʃənz/ ] | 偏差 |
The amount by which a single measurement differs from a fixed value such as the mean.
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| hydrophobic | [ /ˌhaɪdrəˈfoʊbɪk/ ] | 疏水的 adj. |
In chemistry, hydrophobicity is the physical property of a molecule (known as a hydrophobe) that is seemingly repelled from a mass of water.(Strictly speaking, there is no repulsive force involved; it is an absence of attraction.) In contrast, hydrophiles are attracted to water.
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| hydrophilic | [ /ˌhaɪdrəˈfɪlɪk/ ] | 亲水的 adj. |
Tending to dissolve in, mix with, or be wetted by water: a hydrophilic colloid. The opposite of hydrophobic.
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| catalyze | [ /ˈkætəˌlaɪz/ ] | 催化 v. |
Cause or accelerate (a reaction) by acting as a catalyst.
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| Enzyme | [ /ˈɛnˌzaɪm/ ] | 酶 |
Enzymes /ˈɛnzaɪmz/ are macromolecular biological catalysts. Enzymes accelerate chemical reactions. The molecules upon which enzymes may act are called substrates and the enzyme converts the substrates into different molecules known as products. Almost all metabolic processes in the cell need enzyme catalysis in order to occur at rates fast enough to sustain life.
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| covalent bonding | [ /koʊˈveɪlənt ˈbɑndɪŋ/ ] | 共价键 |
Covalent bond, in chemistry, the interatomic linkage that results from the sharing of an electron pair between two atoms. The binding arises from the electrostatic attraction of their nuclei for the same electrons.
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| polyatomic | [ /pˌɑːliːətˈɑːkəm/ ] | 多原子的 |
A polyatomic ion is an ion consisting of multiple atoms associated together by covalent bonds which can be considered as acting as a single unit in the context of acid/base chemistry or in the formation of salts.
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| polarity | [ /poʊˈlɛrəti/ ] | 极性 |
In chemistry, polarity is a separation of electric charge leading to a molecule or its chemical groups having an electric dipole or multipole moment. Polar molecules must contain polar bonds due to a difference in electronegativity between the bonded atoms.
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| electron pair | [ /ˌɪˈlɛktrɑn pɛr/ ] | 电子对 |
In chemistry, an electron pair or a Lewis pair consists of two electrons that occupy the same molecular orbital but have opposite spins. The electron pair concept was introduced in a 1916 paper of Gilbert N. Lewis.
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| oxidation number | [ /ˌɑksəˈdeɪʃən ˈnəmbər/ ] | 氧化数 |
Oxidation number, also called Oxidation State, the total number of electrons that an atom either gains or loses in order to form a chemical bond with another atom.
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| bond strength | [ /bɑnd strɛŋθ/ ] | 键强度 |
In chemistry, bond energy (E) or bond enthalpy (H) is the measure of bond strength in a chemical bond. IUPAC defines bond energy as the average value of the gas-phase bond dissociation energies (usually at a temperature of 298 K) for all bonds of the same type within the same chemical species.
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| bond length | [ /bɑnd lɛŋθ/ ] | 键长 |
In molecular geometry, bond length or bond distance is the average distance between nuclei of two bonded atoms in a molecule. It is a transferable property of a bond between atoms of fixed types, relatively independent of the rest of the molecule.
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| bond energy | [ /bɑnd ˈɛnərʤi/ ] | 键能 |
In chemistry, bond energy (E) or bond enthalpy (H) is the measure of bond strength in a chemical bond. IUPAC defines bond energy as the average value of the gas-phase bond dissociation energies (usually at a temperature of 298 K) for all bonds of the same type within the same chemical species.
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P.15 |
| single bond | [ /ˈsɪŋgəl bɑnd/ ] | 单键 |
In chemistry, a single bond is a chemical bond between two atoms involving two valence electrons. That is, the atoms share one pair of electrons where the bond forms. Therefore, a single bond is a type of covalent bond.
|
P.16 |
| triple bond | [ /ˈtrɪpəl bɑnd/ ] | 三键 |
A triple bond in chemistry is a chemical bond between two atoms involving six bonding electrons instead of the usual two in a covalent single bond. The most common triple bond that is between two carbon atoms can be found in alkynes.
|
P.16 |
| double bond | [ /ˈdəbəl bɑnd/ ] | 双键 |
A double bond in chemistry is a chemical bond between two chemical elements involving four bonding electrons instead of the usual two. The most common double bond that is between two carbon atoms can be found in alkenes.
|
P.16 |
| potential energy | [ /pəˈtɛnʃəl ˈɛnərʤi/ ] | 势能 |
Chemical potential energy is energy that is stored in atoms and the bonds between atoms and can be released by various chemical reactions. An example that most people are familiar with is the energy released when fossil fuels such as gasoline are burned.
|
P.16 |
| kinetic energy | [ /kɪˈnɛtɪk ˈɛnərʤi/ ] | 动能 |
Kinetic energy is a form of energy which is possessed by one during its relative motion.
|
P.16 |
| internal energy | [ /ˌɪnˈtərnəl ˈɛnərʤi/ ] | 内能 |
The total energy of a closed system, the sum of potential energy and its kinetic energy.
|
P.16 |
| diatomic | [ /ˌdaɪəˈtɑmɪk/ ] | 双原子的 |
Having two atoms in the molecule.
|
P.16 |
| binary compounds | [ /ˈbaɪnəˌri ˈkɑmpaʊndz/ ] | 二元化合物 |
In chemistry, a binary compound is something consisting of precisely two elements.
|
P.16 |
| repulsive | [ /riˈpəlsɪv/ ] | 排斥的 adj. |
Relating to repulsion between physical objects.
|
P.16 |
| intramolecular forces | [ /ˌɪntrəməlˈuːkɪkɔːl ˈfɔrsɪz/ ] | 分子内作用力 |
An intramolecular force is any force that holds together the atoms making up a molecule or compound. They contain all types of chemical bond. They are stronger than intermolecular forces, which are present between atoms or molecules that are not actually bonded.
|
P.16 |
| octet rule | [ /ɑkˈtɛt rul/ ] | 八隅规则 |
A stable group of eight electrons occupying a single shell in an atom.
|
P.16 |
| aqueous | [ /ˈeɪkwiəs/ ] | 水溶液的 adj. |
Of or containing water, typically as a solvent or medium.
|
P.16 |
| insoluble | [ /ˌɪnˈsɑljəbəl/ ] | 不可溶解的 adj. |
(of a substance) Incapable of being dissolved.
|
P.16 |
| metallic bonding | [ /məˈtælɪk ˈbɑndɪŋ/ ] | 金属键 |
Metallic bonding arises from the electrostatic attractive force between conduction electrons (in the form of an electron cloud of delocalized electrons) and positively charged metal ions. It may be described as the sharing of free electrons among a lattice of positively charged ions (cations).
|
P.16 |
| delocalized electrons | [ /dˈɛləkəlˌaɪzd ˌɪˈlɛktrɑnz/ ] | 离域电子 |
In chemistry, delocalized electrons are electrons in a molecule, ion or solid metal that are not associated with a single atom or a covalent bond.
|
P.16 |
| brittle | [ /ˈbrɪtəl/ ] | 脆的 adj. |
Hard but liable to break or shatter easily.
|
P.16 |
| luster | [ /ˈləstər/ ] | 金属光泽 |
A gentle sheen or soft glow, especially that of a partly reflective surface.
|
P.16 |
| conductor | [ /kənˈdəktər/ ] | 导体 |
A material or device that conducts or transmits heat, electricity, or sound, especially when regarded in terms of its capacity to do this.
|
P.16 |
| alloy | [ /ˈæˌlɔɪ/ ] | 合金 |
A metal made by combining two or more metallic elements, especially to give greater strength or resistance to corrosion.
|
P.16 |
| Lewis diagram | [ /ˈluːɪs ˈdaɪəˌgræm/ ] | 路易斯结构图 |
Lewis structures, also known as Lewis dot diagrams, Lewis dot formulas, Lewis dot structures, electron dot structures, or Lewis electron dot structures (LEDS), are diagrams that show the bonding between atoms of a molecule and the lone pairs of electrons that may exist in the molecule.
|
P.17 |
| VSEPR model | [ /vˈɛspər ˈmɑdəl/ ] | VSEPR 模型 |
Valence Shell Electron Pair Repulsion (VSEPR) theory is a model used, in chemistry, to predict the geometry of individual molecules from the number of electron pairs surrounding their central atoms. It is also named Gillespie–Nyholm theory after its two main developers. The acronym "VSEPR" is pronounced either "ves-per" or "vuh-seh-per" by some chemists.
|
P.17 |
| lone pairs | [ /loʊn pɛrz/ ] | 孤电子对 |
In chemistry, a lone pair refers to a pair of valence electrons that are not shared with another atom and is sometimes called a non-bonding pair. Lone pairs are found in the outermost electron shell of atoms. They can be identified by using a Lewis structure. Electron pairs are therefore considered lone pairs if two electrons are paired but are not used in chemical bonding.
|
P.17 |
| bond order | [ /bɑnd ˈɔrdər/ ] | 键级 |
Bond order is the number of chemical bonds between a pair of atoms. For example, in diatomic nitrogen N≡N the bond order is 3, in acetylene H−C≡C−H the bond order between the two carbon atoms is also 3, and the C−H bond order is 1. Bond order gives an indication of the stability of a bond.
|
P.17 |
| resonance | [ /ˈrɛzənəns/ ] | 共振 |
In chemistry, resonance or mesomerism is a way of describing delocalized electrons within certain molecules or polyatomic ions where the bonding cannot be expressed by one single Lewis structure. A molecule or ion with such delocalized electrons is represented by several contributing structures (also called resonance structures or canonical structures).
|
P.17 |
| formal charge | [ /ˈfɔrməl ʧɑrʤ/ ] | 形式电荷 [注: 原PDF误作正式电荷] |
In chemistry, a formal charge (FC) is the charge assigned to an atom in a molecule, assuming that electrons in all chemical bonds are shared equally between atoms, regardless of relative electronegativity.
|
P.17 |
| Hybrid Orbital Theory | [ /ˈhaɪbrɪd ˈɔrbətəl ˈθɪri/ ] | 杂化轨道理论 |
In chemistry, orbital hybridisation (or hybridization) is the concept of mixing atomic orbitals into new hybrid orbitals (with different energies, shapes, etc., than the component atomic orbitals) suitable for the pairing of electrons to form chemical bonds in valence bond theory.
|
P.17 |
| hybridization | [ /ˌhaɪbrɪdaɪˈzeɪʃən/ ] | 杂化 |
In chemistry, hybridisation (or hybridization) is the concept of mixing atomic orbitals into new hybrid orbitals (with different energies, shapes, etc., than the component atomic orbitals) suitable for the pairing of electrons to form chemical bonds in valence bond theory. Hybrid orbitals are very useful in the explanation of molecular geometry and atomic bonding properties.
|
P.17 |
| Sigma bonds | [ /ˈsɪgmə bɑndz/ ] | sigma 键 |
In chemistry, sigma bonds (σ bonds) are the strongest type of covalent chemical bond. They are formed by head-on overlapping between atomic orbitals. Sigma bonding is most simply defined for diatomic molecules using the language and tools of symmetry groups. In this formal approach, a σ-bond is symmetrical with respect to rotation about the bond axis.
|
P.17 |
| Pi bond (π bond) | [ /paɪ bɑnd/ ] | π 键 |
Pi bond. In chemistry, pi bonds (π bonds) are covalent chemical bonds where two lobes of an orbital on one atom overlap two lobes of an orbital on another atom.
|
P.17 |
| tetrahedral | [ /ˌtɛtrəˈhidrəl/ ] | 四面体 |
A solid having four plane triangular faces; a triangular pyramid.
|
P.17 |
| trigonal pyramidal | [ /trˈɪɡənəl pərˈæmədəl/ ] | 三角锥体 |
In chemistry, a trigonal pyramid is a molecular geometry with one atom at the apex and three atoms at the corners of a trigonal base. When all three atoms at the corners are identical, the molecule belongs to point group C3v. Some molecules and ions with trigonal pyramidal geometry are ammonia (NH3), xenon trioxide, XeO3, the chlorate ion, ClO3, and the sulfite ion, SO3.
|
P.17 |
| bent | [ /bɛnt/ ] | V 型 adj. |
Sharply curved or having an angle.
|
P.17 |
| linear | [ /ˈlɪniər/ ] | 线型 adj. |
Arranged in or extending along a straight or nearly straight line.
|
P.18 |
| isomer | [ /ˈaɪsəmər/ ] | 同分异构体 |
Each of two or more compounds with the same formula but a different arrangement of atoms in the molecule and different properties.
|
P.18 |
| electron domains | [ /ˌɪˈlɛktrɑn doʊˈmeɪnz/ ] | 电子域 |
In chemistry, the electron domain refers to the number of lone pairs or bond locations around a particular atom in a molecule. Electron domains may also be called electron groups. Bond location is independent of whether the bond is a single, double or triple bond.
|
P.18 |
| molten | [ /ˈmoʊltən/ ] | 熔融 adj. |
(especially of materials with a high melting point, such as metal and glass) Liquefied by heat.
|
P.18 |
| exothermic | [ /ˌɛksoʊˈθərmɪk/ ] | 放热的 adj. |
(of a reaction or process) Accompanied by the release of heat.
|
P.18 |
| ductile | [ /ˈdəktəl/ ] | 可延展的 adj. |
(of a metal) Able to be drawn out into a thin wire.
|
P.18 |
| malleable | [ /ˈmæliəbəl/ ] | 可塑的 adj. |
(of a metal or other material) Able to be hammered or pressed permanently out of shape without breaking or cracking.
|
P.18 |
| graphite | [ /ˈgræˌfaɪt/ ] | 石墨 |
A gray crystalline allotropic form of carbon which occurs as a mineral in some rocks and can be made from coke. It is used as a solid lubricant, in pencils, and as a moderator in nuclear reactors.
|
P.18 |
| semiconductor | [ /ˌsɛmɪkənˈdəktər/ ] | 半导体 |
Semiconductors are crystalline or amorphous solids with distinct electrical characteristics. They are of high resistance-higher than typical resistance materials, but still of much lower resistance than insulators. Their resistance decreases as their temperature increases, which is behavior opposite to that of a metal.
|
P.18 |
| transistor | [ /trænˈzɪstər/ ] | 晶体管 |
A transistor is a semiconductor device used to amplify or switch electronic signals and electrical power. It is composed of semiconductor material with at least three terminals for connection to an external circuit. A voltage or current applied to one pair of the transistor's terminals changes the current through another pair of terminals.
|
P.18 |
| molecular solids | [ /məˈlɛkjələr ˈsɑlədz/ ] | 分子固体 |
A molecular solid is a type of solid in which molecules are held together by van der Waals forces rather than by ionic or covalent bonds.
|
P.18 |
| net-ionic equation | [ /nˈɛtiːˈɑːnɪk ɪkˈweɪʒən/ ] | 净离子方程式 |
A Net Ionic Equation is a chemical equation for a reaction which lists only those species participating in the reaction.
|
P.18 |
| percent ionization | [ /pərˈsɛnt ˌaɪənəˈzeɪʃən/ ] | 解离百分比 |
The percent ionization is the amount or percentage of a weak acid that exists as ions in a particular concentration. Strong acids and bases isolate altogether into ions in a solution, while weak acids and bases do not.
|
P.18 |
| theoretical yield | [ /ˌθiərˈɛtɪkəl jild/ ] | 理论产量 |
Maximum amount of a specified product that could be obtained from specified amounts of reactants, assuming complete consumption of limiting reactant according to only one reaction and complete recovery of product.
|
P.18 |
| endpoint | [ /ˈɛndˌpɔɪnt/ ] | 滴定终点 |
The point in a titration at which a reaction is complete, often marked by a color change.
|
P.18 |
| molarity | [ /moʊˈlærəti/ ] | 摩尔体积浓度 |
Molarity is the most commonly used term to describe the concentration of a solution. It is equal to the moles of solute divided by the liters of solution. The solute is defined as the substance being dissolved, while the solvent is the substance where the solute is dissolved (usually water).
|
P.18 |
| synthesis | [ /ˈsɪnθəsəs/ ] | 合成 |
Chemical synthesis means using chemical reactions to get a product, or several products. This happens by physical and chemical manipulations. Often, several different chemical reactions are used; one after another.
|
P.18 |
| decomposition | [ /ˌdikəmpəˈzɪʃən/ ] | 分解 |
Chemical decomposition, analysis or breakdown is the separation of a single chemical compound into its two or more elemental parts or to simpler compounds. Chemical decomposition is usually regarded and defined as the exact opposite of chemical synthesis.
|
P.18 |
| Arrhenius Concept of Acids and Bases | [ /ɑːˈreɪniəs ˈkɑnsɛpt əv ˈæsədz ənd ˈbeɪsɪz/ ] | 阿伦尼乌斯酸碱理论 |
In 1884, Ar Svante Arrhenius, a Swedish chemist proposed a new theory of acids and bases known as Arrhenius concept of acids and bases. According to Arrhenius concept: an acid is a substance which dissociates in an aqueous solution to give hydrogen ions.
|
P.19 |
| Brønsted–Lowry Concept of Acids and Bases | [ /bˈiːr stˈɛnd ˈlaʊri ˈkɑnsɛpt əv ˈæsədz ənd ˈbeɪsɪz/ ] | 质子酸碱论 |
Brønsted–Lowry theory, also called proton theory of acids and bases, a theory, introduced independently in 1923 by the Danish chemist Johannes Nicolaus Brønsted and the English chemist Thomas Martin Lowry, stating that any compound that can transfer a proton to any other compound is an acid, and the compound that accepts the proton is a base.
|
P.19 |
| Lewis Concept of Acids and Bases | [ /ˈluːɪs ˈkɑnsɛpt əv ˈæsədz ənd ˈbeɪsɪz/ ] | 路易斯酸碱理论 |
In 1923, American chemist Gilbert Newton Lewis proposed generalized definitions for acids that do not restrict them to compounds containing hydrogen but in terms of the structure of acids and bases. Lewis defined an acid as any molecular or ionic species that contains an atom capable of sharing a pair of electrons furnished by a base.
|
P.19 |
| electron-pair acceptor | [ /ɪlˈɛktrəprˈeɪn əksˈɛptər/ ] | 电子对接受体 |
An electron acceptor is a chemical entity that accepts electrons transferred to it from another compound. It is an oxidizing agent that, by virtue of its accepting electrons, is itself reduced in the process.
|
P.19 |
| oxidation-reduction (redox) reaction | [ /ˌɑːksədˌɪziːtˈeɪʃən riˈækʃən/ ] | 氧化还原反应 |
A redox reaction (reduction and oxidation reaction) is a reaction in which there is a transfer of electrons. When an element is reduced, it gains electrons and its oxidation number is reduced.
|
P.19 |
| valence | [ /ˈveɪləns/ ] | 化合价 |
In chemistry, the valence or valency of an element is a measure of its combining power with other atoms when it forms chemical compounds or molecules. The concept of valence was developed in the second half of the 19th century and was successful in explaining the molecular structure of inorganic and organic compounds.
|
P.19 |
| oxidizing agent | [ /ˈɑksəˌdaɪzɪŋ ˈeɪʤənt/ ] | 氧化剂 |
In chemistry, oxidizing agent has two meanings. In one sense, an oxidizing agent is a chemical species that removes an electron from another species. It is one component in an oxidation-reduction (redox) reaction. In the second sense, an oxidizing agent or an oxidizer is a chemical species that transfers electronegative atoms, usually oxygen, to a substrate.
|
P.19 |
| reducing agent | [ /rɪˈdusɪŋ ˈeɪʤənt/ ] | 还原剂 |
A reducing agent (also called a reductant or reducer) is an element or compound that loses (or "donates") an electron to another chemical species in a redox chemical reaction. Since the reducing agent is losing electrons, it is said to have been oxidized.
|
P.19 |
| half-reaction | [ /hˌælfrˈeɪtʃɪkən/ ] | 半反应 |
A half reaction is obtained by considering the change in oxidation states of individual substances involved in the redox reaction.
|
P.19 |
| flask | [ /flæsk/ ] | 瓶 |
A container for liquids.
|
P.19 |
| precipitate | [ /prɪˈsɪpɪˌteɪt/ ] | 沉淀 v. |
A substance precipitated from a solution.
|
P.19 |
| Endothermic | [ /ˌɛndoʊˈθərmɪk/ ] | 吸热的 adj. |
(of a reaction or process) Accompanied by or requiring the absorption of heat. The opposite of exothermic.
|
P.19 |
| reaction coordinate | [ /riˈækʃən koʊˈɔrdəˌneɪt/ ] | 反应坐标 |
In chemistry, a reaction coordinate is an abstract one-dimensional coordinate which represents progress along a reaction pathway. It is usually a geometric parameter that changes during the conversion of one or more molecular entities. In molecular dynamics simulations, a reaction coordinate is called collective variable.
|
P.19 |
| thermodynamics | [ /θˌɜːrmədˈiːniːəsk/ ] | 热动力学 |
Thermodynamics is a branch of physics concerned with heat and temperature and their relation to energy and work. It defines macroscopic variables, such as internal energy, entropy, and pressure that partly describe a body of matter or radiation.
|
P.19 |
| electrode potential | [ /ˌɪˈlɛktroʊd pəˈtɛnʃəl/ ] | 电极电势 |
The difference in electric potential between an electrode and the electrolyte with which it is in contact.
|
P.19 |
| volt | [ /voʊlt/ ] | 电压单位 |
One volt is defined as the difference in electric potential between two points of a conducting wire when an electric current of one ampere dissipates one watt of power between those points.
|
P.19 |
| standard state condition | [ /ˈstændərd steɪt kənˈdɪʃən/ ] | 标况 |
In chemistry, the standard state of a material (pure substance, mixture or solution) is a reference point used to calculate its properties under different conditions.
|
P.20 |
| galvanic cells | [ /ɡælˈvænɪk sɛlz/ ] | 原电池 |
A galvanic cell, or voltaic cell, named after Luigi Galvani, or Alessandro Volta respectively, is an electrochemical cell that derives electrical energy from spontaneous redox reactions taking place within the cell.
|
P.20 |
| anode | [ /ˈæˌnoʊd/ ] | 阳极 / (原电池)负极 [注: 发生氧化反应] |
An anode is an electrode through which conventional current flows into a polarized electrical device. A common mnemonic is ACID for "anode current into device". The direction of (positive) electric current is opposite to the direction of electron flow: (negatively charged) electrons flow out the anode to the outside circuit.
|
P.20 |
| cathode | [ /ˈkæˌθoʊd/ ] | 阴极 / (原电池)正极 [注: 发生还原反应] |
A cathode is the electrode from which a conventional current leaves a polarized electrical device. This definition is sometimes remembered using the mnemonic CCD for cathode current departs. A conventional current describes the direction in which positive electronic charges move. Electrons have a negative charge, so the movement of electrons is opposite to the conventional current flow.
|
P.20 |
| intensive property | [ /ˌɪnˈtɛnsɪv ˈprɑpərti/ ] | 强度性质/内涵性质 |
Physical properties of materials and systems can often be categorized as being either intensive or extensive quantities, according to how the property changes when the size (or extent) of the system changes. According to IUPAC, an intensive property is one whose magnitude is independent of the size of the system, whereas an extensive property changes as the amount of size of the material changes.
|
P.20 |
| spontaneity | [ /ˌspɑntəˈniəti/ ] | 自发性 |
A spontaneous process is one that occurs on its own, without any energy input from the outside.
|
P.20 |
| Gibbs free energy | [ /gɪbz fri ˈɛnərʤi/ ] | 吉布斯自由能 |
In thermodynamics, the Gibbs free energy (IUPAC recommended name: Gibbs energy or Gibbs function; also known as free enthalpy to distinguish it from Helmholtz free energy) is a thermodynamic potential that measures the maximum or reversible work that may be performed by a thermodynamic system at a constant temperature and pressure (isothermal, isobaric).
|
P.20 |
| Nernst equation | [ /nˈɜːrnst ɪkˈweɪʒən/ ] | 能斯特方程 |
In electrochemistry, the Nernst equation is an equation that relates the reduction potential of a half-cell (or the total voltage, i.e. the electromotive force, of the full cell) at any point in time to the standard electrode potential, temperature, activity, and reaction quotient of the underlying reactions and species used.
|
P.20 |
| lithium-ion batteries | [ /lˈɪθiːəmjˌuːn ˈbætəriz/ ] | 锂电池 |
The electrodes of a lithium-ion battery are made of lightweight lithium and carbon. Lithium is also a highly reactive element, meaning that a lot of energy can be stored in its atomic bonds. This translates into a very high energy density for lithium-ion batteries. Here is a way to get a perspective on the energy density. A typical lithium-ion battery can store 150 watt-hours of electricity in 1 kilogram of battery.
|
P.20 |
| fuel cells | [ /fjuəl sɛlz/ ] | 燃料电池 |
A fuel cell uses the chemical energy of hydrogen or another fuel to cleanly and efficiently produce electricity. If hydrogen is the fuel, electricity, water, and heat are the only products.
|
P.20 |
| electrolytic cells | [ /ˌɪˌlɛktrəˈlɪtɪk sɛlz/ ] | 电解池 |
An electrolytic cell is an electrochemical cell that undergoes a redox reaction when electrical energy is applied. It is most often used to decompose chemical compounds, in a process called electrolysis—the Greek word lysis means to break up. When electrical energy is added to the system, the chemical energy is increased.
|
P.20 |
| electroplating | [ /ˌɪˈlɛktrəˌpleɪtɪŋ/ ] | 电镀 |
Electroplating is a process that uses electric current to reduce dissolved metal cations so that they form a coherent metal coating on an electrode. The term is also used for electrical oxidation of anions onto a solid substrate, as in the formation silver chloride on silver wire to make silver/silver-chloride electrodes.
|
P.20 |
| salt bridge | [ /sɔlt brɪʤ/ ] | 盐桥 |
A salt bridge, in electrochemistry, is a laboratory device used to connect the oxidation and reduction half-cells of a galvanic cell (voltaic cell), a type of electrochemical cell. It maintains electrical neutrality within the internal circuit, preventing the cell from rapidly running its reaction to equilibrium.
|
P.21 |
| reaction rate | [ /riˈækʃən reɪt/ ] | 反应速率 |
The reaction rate (rate of reaction) or speed of reaction for a reactant or product in a particular reaction is intuitively defined as how fast or slow a reaction takes place. For example, the oxidative rusting of iron under Earth's atmosphere is a slow reaction that can take many years, but the combustion of cellulose in a fire is a reaction that takes place in fractions of a second.
|
P.21 |
| instantaneous rate | [ /ˌɪnstənˈtæniəs reɪt/ ] | 瞬时速度 |
The instantaneous rate of change measures the rate of change, or slope, of a curve at a certain instant. Thus, the instantaneous rate of change is given by the derivative.
|
P.21 |
| collision model | [ /kəˈlɪʒən ˈmɑdəl/ ] | 碰撞模型 |
A collision model is a model of the rate of a reaction showing how the rate is proportional to the number of collisions of reactant molecules.
|
P.21 |
| transition state | [ /trænˈzɪʃən steɪt/ ] | 过渡态 |
The transition state of a chemical reaction is a particular configuration along the reaction coordinate. It is defined as the state corresponding to the highest potential energy along this reaction coordinate. At this point, assuming a perfectly irreversible reaction, colliding reactant molecules always go on to form products. It is often marked with the double dagger symbol (‡).
|
P.21 |
| activation energy | [ /ˌæktəˈveɪʃən ˈɛnərʤi/ ] | 活化能 |
In chemistry, activation energy is a term introduced in 1889 by the Swedish scientist Svante Arrhenius to describe the minimum energy which must be available to a chemical system with potential reactants to result in a chemical reaction. Activation energy may also be defined as the minimum energy required to start a chemical reaction.
|
P.21 |
| rate-determining step | [ /rˌætədmˈɪrɪŋθ stɛp/ ] | 限速步骤 |
The rate determining step is the slowest step of a chemical reaction that determines the speed (rate) at which the overall reaction proceeds.
|
P.21 |
| logarithm | [ /ˈlɑgərˌɪðəm/ ] | 对数 |
In mathematics, the logarithm is the inverse operation to exponentiation. That means the logarithm of a number is the exponent to which another fixed value, the base, must be raised to produce that number. In simple cases the logarithm counts repeated multiplication. For example, the base 10 logarithm of 1000 is 3, as 10 to the power 3 is 1000; the multiplication is repeated three times.
|
P.21 |
| rate constants | [ /reɪt ˈkɑnstənts/ ] | 速率常数 |
The rate constant is a proportionality factor in the rate law of chemical kinetics that relates the molar concentration of reactants to reaction rate. It is also known as the reaction rate constant or reaction rate coefficient and is indicated in an equation by the letter k.
|
P.21 |
| unit | [ /ˈjunɪt/ ] | 单位 |
A quantity chosen as a standard in terms of which other quantities may be expressed. E.g. “a unit of measurement"
|
P.21 |
| half-life | [ /hˈælflˌaɪf/ ] | 半衰期 |
Half-life (t1⁄2) is the time required for the amount of something to fall to half its initial value. The term is very commonly used in nuclear physics to describe how quickly unstable atoms undergo decay, or how long stable atoms survive, and it is also used more generally of any type of exponential or non-exponential decay. The converse of half-life is doubling time.
|
P.21 |
| unimolecular | [ /ˌʌnɪməlˈɑːkɪlər/ ] | 单分子的 adj. |
Consisting of or involving a single molecule.
|
P.21 |
| reaction mechanism | [ /riˈækʃən ˈmɛkəˌnɪzəm/ ] | 反应机制 |
In chemistry, a reaction mechanism is the step by step sequence of elementary reactions by which overall chemical change occurs. A chemical mechanism describes in detail exactly what takes place at each stage of an overall chemical reaction (transformation).
|
P.21 |
| reaction intermediate | [ /riˈækʃən ˌɪnərˈmidiɪt/ ] | 反应中间物 |
An intermediate or reaction intermediate is a substance formed during a middle step of a chemical reaction between reactants and the desired product. Intermediates tend to be extremely reactive and short-lived, so they represent a low concentration in a chemical reaction compared with the amount of reactants or products.
|
P.21 |
| elementary step | [ /ˌɛləˈmɛnʧri stɛp/ ] | 基元反应 |
An elementary process is also called elementary step or elementary reactions. It expresses how actually molecules or ions react with each other. The equation in an elementary step represents the reaction at the molecular level, not the overall reaction.
|
P.22 |
| bimolecular reactions | [ /bɪməlˈuːkɪlər riˈækʃənz/ ] | 双分子反应 |
Chemical reactions in which two particles participate in the elementary events.
|
P.22 |
| Maxwell-Boltzmann thermal distribution | [ /mˌækswˈɜːrləstənt ˈθərməl ˌdɪstrəˈbjuʃən/ ] | 波兹曼分布 |
The Maxwell-Boltzmann equation, which forms the basis of the kinetic theory of gases, defines the distribution of speeds for a gas at a certain temperature. From this distribution function, the most probable speed, the average speed, and the root-mean-square speed can be derived.
|
P.22 |
| bonds forming | [ /bɑndz ˈfɔrmɪŋ/ ] | 键的形成 |
Common types of bonds include ionic, covalent and metallic bonds. The formation of the bond links the two atoms through the strong attractive forces, using a bond, a region where the electrons of the atoms interact with one another.
|
P.22 |
| combustion | [ /kəmˈbəsʧən/ ] | 燃烧 |
Combustion /kəmˈbʌs.tʃən/ or burning is a high-temperature exothermic redox chemical reaction between a fuel and an oxidant, usually atmospheric oxygen that produces oxidized, often gaseous products, in a mixture termed as smoke. Combustion in a fire produces a flame, and the heat produced can make combustion self-sustaining.
|
P.22 |
| activated complex | [ /ˈæktɪˌveɪtɪd ˈkɑmplɛks/ ] | 活化复合物 |
In chemistry an activated complex is defined by the International Union of Pure and Applied Chemistry (IUPAC) as "that assembly of atoms which corresponds to an arbitrary infinitesimally small region at or near the col (saddle point) of a potential energy surface". In other words, it refers to a collection of intermediate structures in a chemical reaction that persist while bonds are breaking and new bonds are forming. It therefore represents not one defined state, but rather a range of transient configurations that a collection of atoms passes through in between clearly defined products and reactants.
|
P.22 |
| magnitude | [ /ˈmægnəˌtud/ ] | 级数，量级 |
The great size or extent of something.
|
P.22 |
| liter | [ /ˈlitər/ ] | 升 |
The litre (SI spelling) or liter (American spelling) (symbols L or l, sometimes abbreviated ltr) is an SI accepted metric system unit of volume equal to 1 cubic decimeter (dm3), 1,000 cubic centimeters (cm3) or 1/1,000 cubic metre. A cubic decimetre (or litre) occupies a volume of 10 cm×10 cm×10 cm (see figure) and is thus equal to one-thousandth of a cubic metre.
|
P.22 |
| exponent | [ /ˈɛkˌspoʊnənt/ ] | 指数 |
A quantity representing the power to which a given number or expression is to be raised, usually expressed as a raised symbol beside the number or expression (e.g. 3 in 23 = 2 × 2 × 2).
|
P.22 |
| multi-step | [ /mˈʌltiːstˌɛk/ ] | 多步骤的 adj. |
Involving two or more distinct steps or stages.
|
P.22 |
| decomposition | [ /ˌdikəmpəˈzɪʃən/ ] | 分解 |
Chemical decomposition, analysis or breakdown is the separation of a single chemical compound into its two or more elemental parts or to simpler compounds. Chemical decomposition is usually regarded and defined as the exact opposite of chemical synthesis.
|
P.22 |
| molar concentration | [ /mˈoʊlər ˌkɑnsənˈtreɪʃən/ ] | 摩尔浓度 |
Molar concentration, also called molarity, amount concentration or substance concentration, is a measure of the concentration of a solute in a solution, or of any chemical species, in terms of amount of substance in a given volume. A commonly used unit for molar concentration used in chemistry is mol/L. A solution of concentration 1 mol/L is also denoted as 1 molar (1 M).
|
P.22 |
| reaction intermediates | [ /riˈækʃən ˌɪnərˈmidiəts/ ] | 反应中间物 |
An intermediate or reaction intermediate is a substance formed during a middle step of a chemical reaction between reactants and the desired product. Intermediates tend to be extremely reactive and short-lived, so they represent a low concentration in a chemical reaction compared with the amount of reactants or products.
|
P.23 |
| bond breaking | [ /bɑnd ˈbreɪkɪŋ/ ] | 化学键断裂 |
Bond breaking and bond forming occur during a chemical reaction. The energy changes in chemical reactions are caused by bond breaking and bond forming. Breaking a bond is endothermic. Energy is taken in to break a chemical bond.
|
P.23 |
| carbonyl group | [ /kˈɑːrbənəl grup/ ] | 羰基 [注: 原PDF误作羟基] |
In organic chemistry, a carbonyl group is a functional group composed of a carbon atom double-bonded to an oxygen atom: C=O. It is common to several classes of organic compounds, as part of many larger functional groups. A compound containing a carbonyl group is often referred to as a carbonyl compound.
|
P.23 |
| Haber process | [ /ˈheɪbər ˈprɔˌsɛs/ ] | 哈伯博斯制氨法 |
The Haber process, also called the Haber–Bosch process, is an artificial nitrogen fixation process and is the main industrial procedure for the production of ammonia today. It is named after its inventors, the German chemists Fritz Haber and Carl Bosch, who developed it in the first half of the 20th century.
|
P.23 |
| in motion | [ /ɪn ˈmoʊʃən/ ] | 动态中 |
Not static; moving.
|
P.23 |
| average kinetic energy | [ /ˈævərɪʤ kɪˈnɛtɪk ˈɛnərʤi/ ] | 平均动能 |
The average kinetic energy of the particles of a substance is determined by the temperature of the medium, using the equation for an ideal gas. If the temperature is unknown, then the average speed and mass of the particles are utilized to determine the average kinetic energy.
|
P.23 |
| kinetic energy | [ /kɪˈnɛtɪk ˈɛnərʤi/ ] | 动能 |
Kinetic energy is the energy an object possesses due to its motion. An object of mass m moving at velocity v has a kinetic energy equal to ½mv2.
|
P.23 |
| thermal equilibrium | [ /ˈθərməl ˌiːkwɪˈlɪbriəm/ ] | 热平衡 |
Thermal equilibrium is when the temperature of a system or organism is equal to the temperature of its surroundings. It is part of the zeroth law of thermodynamics. The zeroth law is that if 2 things are at the same temperature, no heat will flow between them.
|
P.23 |
| specific heat capacity | [ /spɪˈsɪfɪk hit kəˈpæsɪti/ ] | 比热容 |
The quantity of heat that will raise the temperature of 1g of a substance by 1 °C, usually in units of cal g-1 °C-1 or J g-1 °C-1.
|
P.23 |
| heat capacity | [ /hit kəˈpæsɪti/ ] | 热容 |
The amount of energy required to raise the temperature of an object by one degree Celsius (or Kelvin). It is represented by the symbol c and is given in units of J/K.
|
P.23 |
| glycerol | [ /ˈglɪsərˌoʊl/ ] | 甘油 |
A clear, colorless, viscous, sweet-tasting liquid belonging to the alcohol family of organic compounds.
|
P.23 |
| trichloropropane | [ /trˌɪklɑːrˈɔːpərn/ ] | 三氯丙烷 |
Trichloropropane is a synthetic chemical that is also known as allyl trichloride, glycerol trichlorohydrin, and trichlorohydrin. It is a colorless, heavy liquid with a sweet but strong odor. It evaporates very quickly and small amounts dissolve in water.
|
P.23 |
| enthalpy of combustion | [ /ˈɛnθəlpi əv kəmˈbəsʧən/ ] | 燃烧焓 |
The standard enthalpy of combustion is the enthalpy change when one mole of a reactant completely burns in excess oxygen under standard thermodynamic conditions (although experimental values are usually obtained under different conditions and subsequently adjusted).
|
P.23 |
| thermodynamics | [ /θˌɜːrmədˈiːniːəsk/ ] | 热动力学 |
Thermodynamics is a branch of physics concerned with heat and temperature and their relation to energy and work. It defines macroscopic variables, such as internal energy, entropy, and pressure, that partly describe a body of matter or radiation.
|
P.23 |
| electromagnetism | [ /ˌɪˌlɛktroʊˈmægnəˌtɪzəm/ ] | 电磁 |
Electromagnetism is a branch of physics which involves the study of the electromagnetic force, a type of physical interaction that occurs between electrically charged particles. The electromagnetic force usually shows electromagnetic fields, such as electric fields, magnetic fields, and light. The electromagnetic force is one of the four fundamental interactions in nature.
|
P.23 |
| heat exchange | [ /hit ɪksˈʧeɪnʤ/ ] | 热交换 |
Transfer of heat between two or more objects.
|
P.24 |
| The Laws of Thermodynamics | [ /ðə lɔz əv θˌɜːrmədˈiːniːəsk/ ] | 热力学定理 |
The four laws of thermodynamics define fundamental physical quantities (temperature, energy, and entropy) that characterize thermodynamic systems. The laws describe how these quantities behave under various circumstances, and forbid certain phenomena (such as perpetual motion).
|
P.24 |
| phase transition | [ /feɪz trænˈzɪʃən/ ] | 相变 |
A phase transition is the transformation of a thermodynamic system from one phase or state of matter to another one by heat transfer. The term is most commonly used to describe transitions between solid, liquid and gaseous states of matter, and, in rare cases, plasma. A phase of a thermodynamic system and the states of matter have uniform physical properties.
|
P.24 |
| condense | [ /kənˈdɛns/ ] | 冷凝 v. |
Change or cause to change from a gas or vapor to a liquid.
|
P.24 |
| enthalpy of vaporization | [ /ˈɛnθəlpi əv veɪpərəˈzeɪʃən/ ] | 蒸发焓 |
The enthalpy of vaporization, (symbol ∆Hvap) also known as the (latent) heat of vaporization or heat of evaporation, is the energy (enthalpy) that must be added to the substance, typically a liquid, to transform a quantity of that substance into a gas. The enthalpy of vaporization is a function of the pressure at which that transformation takes place.
|
P.24 |
| work | [ /wərk/ ] | 功 |
In physics, a force is said to do work if, when acting on a body, there is a displacement of the point of application in the direction of the force. For example, when a ball is held above the ground and then dropped, the work done on the ball as it falls is equal to the weight of the ball (a force) multiplied by the distance to the ground (a displacement).
|
P.24 |
| heat of reaction | [ /hit əv riˈækʃən/ ] | 反应热 |
The heat of reaction (also known and enthalpy of reaction) is the change in the enthalpy of a chemical reaction that occurs at a constant pressure. It is a thermodynamic unit of measurement useful for calculating the amount of energy per mole either released or produced in a reaction.
|
P.24 |
| calorimeter | [ /kəlˈɔːrəmˌɛtər/ ] | 热量计 |
A calorimeter is an object used for calorimetry, or the process of measuring the heat of chemical reactions or physical changes as well as heat capacity. Differential scanning calorimeters, isothermal microcalorimeters, titration calorimeters and accelerated rate calorimeters are among the most common types.
|
P.24 |
| piston | [ /ˈpɪstən/ ] | 活塞 |
A disk or short cylinder fitting closely within a tube in which it moves up and down against a liquid or gas, used in an internal combustion engine to derive motion, or in a pump to impart motion.
|
P.24 |
| cylinder | [ /ˈsɪlɪndər/ ] | 圆筒/气缸 |
The piston chamber in an engine; a chamber in a pump from which the piston expels the fluid.
|
P.24 |
| bucket | [ /ˈbəkɪt/ ] | 桶 |
A roughly cylindrical open container, typically made of metal or plastic, with a handle, used to hold and carry liquids or other material.
|
P.24 |
| bond enthalpies | [ /bɑnd ɪnθˈɑːlpiːz/ ] | 键焓 |
The bond enthalpy is the energy required to break a chemical bond. It is usually expressed in units of kJ mol-1, measured at 298 K. The exact bond enthalpy of a particular chemical bond depends upon the molecular environment in which the bond exists. Therefore, bond enthalpy values given in chemical data books are averaged values.
|
P.24 |
| isolated system | [ /ˈaɪsəˌleɪtɪd ˈsɪstəm/ ] | 隔离系统 |
An isolated system obeys the conservation law that its total energy–mass stays constant. Most often, in thermodynamics, matter and energy are treated as separately conserved.
|
P.24 |
| ozone | [ /ˈoʊˌzoʊn/ ] | 臭氧 |
Ozone, or trioxygen, is an inorganic molecule with the chemical formula O3. It is a pale blue gas with a distinctively pungent smell. It is an allotrope of oxygen that is much less stable than the diatomic allotrope O2, breaking down in the lower atmosphere to O2 or dioxygen. Ozone is formed from dioxygen by the action of ultraviolet light (UV) and electrical discharges within the Earth's atmosphere. It is present in very low concentrations throughout the latter, with its highest concentration high in the ozone layer of the stratosphere, which absorbs most of the Sun's ultraviolet (UV) radiation.
|
P.24 |
| surroundings | [ /sərˈaʊndɪŋz/ ] | 环境 |
The system is the part of the universe we wish to focus our attention on. In the world of chemistry, the system is the chemical reaction, and the surroundings are everything else in this universe.
|
P.25 |
| open system | [ /ˈoʊpən ˈsɪstəm/ ] | 开放系统 |
An open system can transfer both energy and matter to and from the surroundings.
|
P.25 |
| closed system | [ /kloʊzd ˈsɪstəm/ ] | 封闭系统 |
A closed system is one where energy can be transferred to the surroundings but matter cannot.
|
P.25 |
| dipole-induced dipole force | [ /daɪpˈɑːlədʒənds ˈdaɪˌpoʊl fɔrs/ ] | 偶极-诱导偶极作用力 [注: 原PDF误作偶极-偶极] |
A dipole-induced dipole attraction is a weak attraction that results when a polar molecule induces a dipole in an atom or in a nonpolar molecule by disturbing the arrangement of electrons in the nonpolar species.
|
P.25 |
| dipole moment | [ /ˈdaɪˌpoʊl ˈmoʊmənt/ ] | 偶极矩 |
A measure of the polarity in a chemical bond or molecule, equal to the product of one charge and the distance between the charges.
|
P.25 |
| nonane | [ /nˈɑːnən/ ] | 壬烷; |
A colorless liquid hydrocarbon of the alkane series, present in petroleum spirit.
|
P.25 |
| repulsions | [ /riːpˈʌlʃənz/ ] | 排斥力 |
A force under the influence of which objects tend to move away from each other, e.g. through having the same magnetic polarity or electric charge.
|
P.25 |
| hydrogen bonding | [ /ˈhaɪdrəʤən ˈbɑndɪŋ/ ] | 氢键 |
The definition of hydrogen bond is a chemical bond between the hydrogen atom and an electronegative atom. An example of hydrogen bond is water molecules bonding together in the form of ice.
|
P.25 |
| electrostatic forces | [ /ˌɪˌlɛktroʊˈstætɪk ˈfɔrsɪz/ ] | 静电力 |
Electrostatic force is the force that occurs between electrically charged objects. The Force existing between two charged particles is known as electrostatic force. Example of it would be: plastic rubber.
|
P.25 |
| hydration energy | [ /haɪˈdreɪʃən ˈɛnərʤi/ ] | 水合能 |
Hydration energy (also hydration enthalpy) is the amount of energy released when one mole of ions undergo hydration. It is a special case of dissolution energy, with the solvent being water. For example, upon dissolving a salt in water, the outermost ions (those at the edge of the lattice) move away from the lattice and become covered with the neighboring water molecules.
|
P.25 |
| polarizable | [ /pˈoʊlərəzəz/ ] | 可被极化的 adj. |
Polarizability is the ability to form instantaneous dipoles. It is a property of matter. Polarizabilities determine the dynamical response of a bound system to external fields, and provide insight into a molecule's internal structure.
|
P.25 |
| thymine | [ /ˈθaɪmiːn/ ] | 胸腺嘧啶 |
A compound which is one of the four constituent bases of nucleic acids. A pyrimidine derivative, it is paired with adenine in double-stranded DNA.
|
P.25 |
| adenine | [ /ˈædənɪn/ ] | 腺嘌呤 |
A compound which is one of the four constituent bases of nucleic acids. A purine derivative, it is paired with thymine in double-stranded DNA.
|
P.25 |
| base pairs | [ /beɪs pɛrz/ ] | 碱基对 |
A base pair (bp) is a unit consisting of two nucleobases bound to each other by hydrogen bonds. They form the building blocks of the DNA double helix, and contribute to the folded structure of both DNA and RNA.
|
P.25 |
| DNA strand | [ /ˈdiˌɛˈneɪ strænd/ ] | DNA 链 |
A long linear polymer found in the nucleus of a cell and formed from nucleotides and shaped like a double helix; associated with the transmission of genetic information.
|
P.25 |
| electron cloud | [ /ˌɪˈlɛktrɑn klaʊd/ ] | 电子云 |
An electron cloud is the region of negative charge surrounding an atomic nucleus that is associated with an atomic orbital. It is defined mathematically, describing a region with a high probability of containing electrons.
|
P.25 |
| disorder | [ /dɪˈsɔrdər/ ] | 混乱/无序 |
A lack of order or regular arrangement; disarray; confusion.
|
P.25 |
| dehydration of ethanol | [ /ˌdihaɪˈdreɪʃən əv ˈɛθəˌnɔl/ ] | 乙醇脱水 |
The dehydration of ethanol to give ethene. Ethanol is heated with an excess of concentrated sulphuric acid at a temperature of 170°C. The gases produced are passed through sodium hydroxide solution to remove the carbon dioxide and sulphur dioxide produced from side reactions.
|
P.25 |
| dissolution | [ /ˌdɪsəˈluʃən/ ] | 溶解 |
The dissolution of gases, liquids, or solids into a liquid or other solvent is a process by which these original states become solutes (dissolved components), forming a solution of the gas, liquid, or solid in the original solvent.
|
P.25 |
| thermodynamic | [ /θˌɜːrmədiːnˈæmɪk/ ] | 热力的 adj. |
The branch of physical science that deals with the relations between heat and other forms of energy (such as mechanical, electrical, or chemical energy), and, by extension, of the relationships between all forms of energy.
|
P.26 |
| spontaneous | [ /spɑnˈteɪniəs/ ] | 自发的 adj. |
(of a process or event) Occurring without apparent external cause.
|
P.26 |
| barrier | [ /ˈbɛriər/ ] | 障碍 |
Anything serving to obstruct passage or to maintain separation.
|
P.26 |
| reaction quotient (Qr) | [ /riˈækʃən kˈwoʊʃənt/ ] | 反应商 |
In chemistry, a reaction quotient (Qr) is a function of the activities or concentrations of the chemical species involved in a chemical reaction. In the special case that the reaction is at equilibrium the reaction quotient is constant and equal to the equilibrium constant which appears in the expression of the law of mass action.
|
P.26 |
| physical state | [ /ˈfɪzɪkəl steɪt/ ] | 物理状态 |
In physics, a state of matter is one of the distinct forms in which matter can exist. Four states of matter are observable in everyday life: solid, liquid, gas, and plasma. Many other states are known to exist, such as glass or liquid crystal, and some only exist under extreme conditions, such as Bose–Einstein condensates, neutron-degenerate matter, and quark-gluon plasma, which only occur, respectively, in situations of extreme cold, extreme density, and extremely high-energy. Some other states are believed to be possible but remain theoretical for now.
|
P.26 |
| numerator | [ /nˈuːmərˌeɪtər/ ] | 分子 |
The part of a fraction that is above the line and signifies the number to be divided by the denominator.
|
P.26 |
| denominator | [ /dɪˈnɑməˌneɪtər/ ] | 分母 |
The number below the line in a common fraction; a divisor.
|
P.26 |
| concentration | [ /ˌkɑnsənˈtreɪʃən/ ] | 浓度 |
The relative amount of a given substance contained within a solution or in a particular volume of space; the amount of solute per unit volume of solution.
|
P.26 |
| solubility product constant | [ /ˌsɑːljʊˈbɪləti ˈprɑdəkt ˈkɑnstənt/ ] | 溶度积常数 |
Solubility product constant is simplified equilibrium constant (Ksp) defined for equilibrium between a solids and its respective ions in a solution. Its value indicates the degree to which a compound dissociates in water.
|
P.26 |
| condensation | [ /ˌkɑndənˈseɪʃən/ ] | 缩合/冷凝 |
1. A reaction in which two molecules combine to form a larger molecule, producing a small molecule such as H2O as a byproduct. 2. It can also mean the conversion of a vapor or gas to a liquid.
|
P.26 |
| molarity | [ /moʊˈlærəti/ ] | 摩尔体积浓度 |
The number of moles of solute per liter of solution.
|
P.26 |
| diprotic acid | [ /daɪprˈɑːtɪk ˈæsəd/ ] | 二元酸 |
Any acid with two hydrogen atoms in its molecule that are capable of being released or ionized in water, such as sulphuric acid and carbonic acid.
|
P.26 |
| triprotic acid | [ /traɪprˈoʊtɪk ˈæsəd/ ] | 三元酸 |
An acid that has three ionizable hydrogen atoms in each molecule.
|
P.26 |
| stepwise dissociation | [ /stˈɛpwˌaɪz dɪˌsoʊsiˈeɪʃən/ ] | 分步电离 |
A stepwise reaction is a chemical reaction with one or more reaction intermediates and involving at least two consecutive elementary reactions.
|
P.26 |
| oxyacid | [ /ˈɑːksədˌeɪsɪk/ ] | 含氧酸 |
An oxyacid, or oxoacid, is an acid that contains oxygen. Specifically, it is a compound that contains hydrogen, oxygen, and at least one other element, with at least one hydrogen atom bond to oxygen that can dissociate to produce the H+ cation and the anion of the acid.
|
P.26 |
| spectator ion | [ /ˈspɛkteɪtər aɪən/ ] | 不相关离子 |
A spectator ion is an ion that exists as a reactant and a product in a chemical equation.
|
P.26 |
| amphiprotic | [ /ˌæmfɪˈprɑːtɪk/ ] | 两性的 adj. |
In chemistry, an amphoteric compound is a molecule or ion that can react both as an acid as well as a base. Many metals (such as copper, zinc, tin, lead, aluminium, and beryllium) form amphoteric oxides or hydroxides. Amphoterism depends on the oxidation states of the oxide. Al2O3 is an example of an amphoteric oxide.
|
P.26 |
| equivalence point | [ /ɪkˈwɪvələns pɔɪnt/ ] | 当量点 |
The equivalence point, or stoichiometric point, of a chemical reaction is the point at which chemically equivalent quantities of bases and acids have been mixed. In other words, the moles of acid are equivalent to the moles of base, according to the equation (this does not necessarily imply a 1:1 molar ratio of acid:base, merely that the ratio is the same as in the equation). It can be found by means of an indicator, for example phenolphthalein or methyl orange.
|
P.27 |
| pH | [ /ˈpiˈeɪʧ/ ] | 酸碱度 |
A figure expressing the acidity or alkalinity of a solution on a logarithmic scale on which 7 is neutral, lower values are more acid and higher values more alkaline.
|
P.27 |
| dissolution | [ /ˌdɪsəˈluʃən/ ] | 融化，溶解 |
The dissolution of gases, liquids, or solids into a liquid or other solvent is a process by which these original states become solutes (dissolved components), forming a solution of the gas, liquid, or solid in the original solvent.
|
P.27 |
| Lewis electron-dot diagrams | [ /ˈluːɪs ɪlˈɛktrəndˌɑːt ˈdaɪəˌgræmz/ ] | 路易斯点式 |
Lewis Electron Dot Diagrams are used to visually depict bonding by representing valence electrons as dots surrounding an elemental symbol. These dots can be on any of the four sides of the symbol, each side representing a different orbital.
|
P.27 |