【标准】alevel化学常用单词汇总
【关键字】标准
chapter 1 atomic structure
element n.元素
all know materials can be broken down into fundamental substances we call element.
我们所知道的所有物质都可以分解成原子。
atom n.原子
atom is the smallest particle of matter having all that element’s characteristics.
原子时具有元素性质的最小粒子。
nucleus /’nju:kli?s，’nu?kli?s/ 原子核
electron n.电子
proton 质子
neutron 中子
compound n. 化合物：
When two or more elements combine and form a compound, a chemical change takes place.
当两种或两种以上的元素结合形成化合物时, 发生化学变化。
化学中的物质分为单质和化合物，大部分元素是以化合物的形式存在的。
ion n. 离子：
when an atom get or lost elections,it becomes ion.
原子得失电子后形成离子。
cathode n. 阴极（negative electrode）
Cathode rays are attracted by a positive charge.
阴极射线被阳电荷所吸引。
anode n. 阳极（positive election）
A red wire is often attached to the anode.
红色电线通常与阳极相联。
particle n. 粒子：
Particles include moleculars,atoms , protons, neutrons ,electrons and ions.微小粒子包括分子，原
子，质子，中子，电子，离子等等。
ionisation n. 电离,离子化：
We can get some elementary substance by ionisation.
可以通过电离的方法来制取某些单质。
ionisation energy n.电离能：
the energy needed to remove 1 mol of electrons from 1 mol of gaseous atoms .
从原子中移走一个电子所需要的能量。
First ionisation energy n.第一电离能
the energy required to remove one electron from each atom in one mole of gaseous atoms is called first ionisation energy,?Hi1（2010年真题）
as: Ca(g)→Ca+(g)+e-;?Hi1=+590KJ/mol
isotope n.同位素：
which element have same number of protons ,but different number of neutrons.
有相同质子数的元素就是同位素。
shielding effect n.屏蔽效应:
electrons in the filled inner shells repel electrons in the outer shell and reduce the effect of the positive nuclear ,this is called shielding effect.
电子都是带负电荷的所以外层的电子受到内层电子的一个排斥力，这就是屏蔽效应。
chapter2 atoms molecules and stoichiometry
Relative mass n. 相对质量
The actual mass of an atom is very small (in the range of 10-20 kg ,for C atomic mass is 1.933×10-20g ). Hence relative mass( where the mass of
an atom is compared with the mass of one reference atom) is used instead.因为原子本身的质量很小，计算使用都很不方便，因此我们采用一个相对质量，用质量和一个标准物质作比较。
relative atomic mass n.相对原子质量：
elative atomic mass is the mass of an atom relative to 1/12 times the mass of carbon-12, relative atomic mass is a ratio,it has no unit.
相对原子质量就是物质的质量与C-12 原子的1/12 的一个比值。相对原子质量是一个比值，没有单位。
relative isotopic mass n. 相对同位素质量
relative isotope mass is the mass of one atom of the isotope relative to 1/12 times the mass of one atom of carbon-12.
相对同位素质量就是用同位素的质量和1/12 C-12原子的质量相比的一个比值。
relative molecular mass n. 相对分子质量
As we all know moleculars are all made by atoms so we can get the relative molecular mass by adding up the relative atomic mass of all the atoms present in the molecule.
相对分子质量就是组成分子的各元素的相对原子质量之和。
avogadro’s constant n. 阿伏伽德罗常数：
The number of atoms in exactly 12g of carbon -12 is 6.02×1023，the number is called avogadro’s constant .
12克C-12 所含原子的个数是6.02×1023，这个数就是阿伏伽德罗常数
empirical formulae n.实验式：
empirical formulae of a compound shows the simplest whole number ratio of the element present.
实验式表示的是分子中原子的最简单组成。
molecular formulae n.分子式
molecular formulae shows the total number of atoms of each element present in a molecule of the compound.
分子式表示的是分子中原子的组成。
titration 滴定：
A titration is a way of measuring quantities of reactants.
滴定反应是定量测定的一种方法
halogen 卤素：
在元素周期表中含fluorine氟，chlorine 氯，bromine溴，iodine 碘，
astatine 砹五种卤素
precipitation n.沉淀:
it is a solid.是一种固体物质。两种离子结合后形成一种微溶或不溶物沉淀下来。
dilute vt稀释：
adding water or something else to decrease the molarities.在溶液中加水或加入其它溶剂使溶液浓度变低。The water will dilute the wine.水能使酒变淡。
Molarity n.摩尔浓度：
the mol of the substance divided by the volume of the solution ，the unit is mol/dm-3.
浓度比上体积就得到我们的摩尔浓度，单位是mol/dm-3
chapter3 化学键
ionic bond n.离子键
The electrostatic attraction between positive ion and negative ion is called ionic bond.
正负离子之间的引力成为离子键，如NaCl
covalent bond n.共价键
A covalent bond is formed when electrons are shared between two atoms. 两个原子共用电子形成共价键，如O2
metallic bond n.金属键
Metallic bond is an attractive forces between the positive ions and the delocalized electrons.
金属键就是金属阳离子和自由电子（离域电子）之间的作用力，它的大小和金属最外层电子数有关，电子数越多，金属键越强。
co-ordinate bond n.配位键
In the co-ordinate bond ,one atom provides two electrons that are shared with another atom.thus,the donor atom must have a lone pair of electrons while the acceptor atom must have an empty orbital to accommodate the electrons.
一个原子提供一对电子，另一个原子提供一个空轨道。
hydrogen bond n. 氢键
Hydrogen bond are usually represented by three dashes: fluorine, oxygen, nitrogen and it is a very strong dipole-dipole attraction.
Such as in water:the oxygen atoms have lone pairs of electrons,the hydrogen atom has almost lost both the shared electrons to the oxygen to
which it is covalently bonded and this leaves it almost bare of electron.
实际上氢键也是一种静电引力，形成氢键的分子中必须带有孤电子对，电负性很大，而且原子半径很小（如N,F,O）。考试时要把元素中的孤对电子标出，把分子中的极性标出，表示出氢键。
Van der waal's forces n.范德华力
Instantaneous dipole-induced dipole forces is called Van der waal's forces.瞬间诱导偶极就是分子间作用力。
VSEPR（valence Shell electron pair repulsion）n. 价层电子互斥理论The shape of simple covalent molecules can be predicted using the valence shell electron-pair repulsion theory. Electron pairs (bond pairs and lone pairs )will repel one anther so that they are as far apart as possible.
孤电子对之间相互排斥，从而使原子呈现一定的空间结构，从而可以根据价层电子对理论来推测分子的空间构型。
permanent dipole /dipole-dipole force n. 永久偶极
The water molecules are attracted to the charged nylon rod or comb because they have a permanent electric dipole .a force of this type is called a dipole -dipole force.
水分子被吸引到了尼龙或梳子上，是因为他们有了一个瞬间的电偶
极。像这种力就被称为由诱导产生的诱导力，也就是永久偶极。
temporary dipole/instantaneous dipole n.瞬时偶极induce dipole n. 诱导偶极
The instantaneous dipole -- induce dipole is rather like the effect of a magnet on a pin .the pin becomes temporarily magnetised and is attracted to the magnet .the strength of the force increase with the number of electrons and protons present.
瞬间诱导偶极就好像靠近磁铁的大头针。大头针有了瞬间的磁性，而被吸引到了磁铁上，这种瞬间的力随着质子数，电子数的增加而增加。
induce vt.引导
Her illness was induced by overwork.
她的病是操劳过度引起的。
polarity 极性
Polarity is inherent in a magnet.
极性是磁铁的固有性质。
chapter4 物质状态
Kinetic energy n. 动能
The kinetic energy of the molecules in a solid ,liquid or gas is a measure
of the amount of random movement of molecules.
分子动能就是固体，液体，气体分子做规则运动的数目。
Evaporation n. 蒸发，发散，消失
Evaporation is a phase transition from the liquid phase to gas phase that occurs at temperatures below the boiling temperature at a given pressure .and evaporation usually occurs on the surface.
蒸发是一个在低于沸点的温度下从液体变为气体的过程，蒸发一般是发生在液体表面。
Vapor pressure n. 气压
Vapor pressure is the pressure of a vapor in equilibrium with its non-vapor phase. All liquid and solid have a tendency to evaporate to a gaseous form , and all gases have a tendency to condense back into their original form .at any given temperature ,for a particular substance ,there is a pressure at which the gas of that substance is in dynamic equilibrium with its liquid or solid forms. This is the vapor pressure of that substance at that temperature.
气压是一种气液平衡状态，液体和固体都有一种蒸发成气态的趋势，所有的气体也都有一种聚集成原始状态的趋势，。在任何给定的温度下，对于一种特殊的物质，都有一种气态和固态或液态成动态平衡的压力。这种压力就被称为在此温度下的气压。
melting vt. 融化
Melting is a physical process that results in the phase change of a substance from a solid to a liquid.
融化是一个从固体变成液体的物理过程。
giant molecular lattices n. 大分子晶体
molecular lattices are three –dimensional arrangement of atoms held together by strong covalent bonds .some giant molecular structures contain atoms of only one element .
这种大分子晶体是通过共价键结合成三维空间排布的晶体。一些大分子晶体只含有一种元素。
giant ionic lattices n. 大离子晶体
in such a lattice ,there is a regular arrangement of anions and cations ,sodium chloride and magnesium oxide form a cubic lattice ,in which each cations is surrounded by six anions and each anions is surrounded by six cations.
在大分子晶体中，阴阳离子呈规则排布，以立方体的氯化钠和氧化镁为例，每个阴离子都被六个阳离子包围，每个阳离子都被六个阴离子包围。
ideal gas law n. 理想气体定律
the behaviour of ideal gases is represented by the ideal gas equation :
PV=nRT p is the pressure ,measured in pascals ,Pa; V is the volume ,measured in metre cubed ,m3; T is the temperature on the Kelvin ;R is the gas constant ,8.314JK-1 mol-1;and n is the
理想气体符合理想气体定律。PV=nRT
Intermolecular force n.分子间作用力
Intermolecular force tend to bring order to the movement of molecules .分子间作用力趋于使分子的运动有序化。
Brownain motion n. 布朗运动
The random movements of the pollen ,known as brownain motion.
花粉的这种有序运动称为布朗运动。
Instantaneous dipole forces n. 瞬时偶极力
van der waal’s forces n. 范德华力
It is one of the features of large molecules that their electron clouds are more spread out , and it is just this type of molecule that has large forces between instantaneous dipoles. There forces are called instantaneous dipole forces ( are also known as van der waal’s forces).
大分子的分子云有一种特点就是他们的分子云会扩散，在他们的瞬间偶极间会产生一种力叫瞬间偶极力（也叫分子间作用力）。
chapter 5 chemical energetics
Exothermic adj. 放热的
Most chemical reactions release energy to their surroundings ,these reactions are described as exothermic.
一些化学反应会向环境释放能量，这种反应称为放热的反应。
Endothermic adj. 吸热的
Some chemical reactions occur only while energy is transferred to them an external source. Reactions such as these which require a heat input are endothermic reactions.
一些化学反应需要从外界环境中吸收能量，这种化学反应为吸热反应。
Ehthalpy n. 焓
Enthalpy is the total energy content of the reacting materials .it is given the symbol H. enthalpy cannot be measured as such , but it is possible to measure the enthalpy change .
焓是反应物中所含有的总能量，用H来表示，焓的数值不能直接测得，但可以测定焓变。
Enthalpy change n. 焓变
Enthalpy change is given the symbol△H ,the units are kilojoules
per mole(Kj/mol).△H= H products- H reactants
Standard conditions n. 标准条件
When we compare the enthalpy changes of various reactions we must use standard conditions. such as known temperature ,pressures , amounts ,and concentrations of reactions or products .
我们在测定不同反应物的焓变时必须是在标准条件下，比如特定的温度，压强，反应物或产物的数目和浓度。
Standard enthalpy change of reaction n. 标准反应焓
The standard enthalpy change of reaction is the enthalpy change when amounts of reactants, as shown in the reaction equation, react together under standard conditions to give products in their standard states.
标准反应焓变就是在反应方程式中的反应物和产物都在标准条件下反应的焓变。
Standard enthalpy change of formation n. 标准生成焓
The standard enthalpy change of formation is the enthalpy change when one mole of a compound is formed from its elements under standard conditions , both compound and elements are in their standard states.
标准生成焓是由标准状态下的元素生成1 mol 化合物的焓变（产物也要在标准状态下）
Standard enthalpy change of combustion n. 标准燃烧含
The standard enthalpy change of combustion is the enthalpy change when one mole of an element or compound reacts completely with oxygen under standard conditions.
标准燃烧含是指在标准状态下1mol 元素或化合物和氧气完全反应的焓变。
Standard enthalpy change of hydration n. 标准水和焓变
The standard enthalpy change of hydration is the enthalpy change when one mole of a gaseous ion dissolves in water to give an infinitely dilute solution .
标准水和焓变就是当 1 mol 气态离子溶解在水中生成水溶液放出的能量。
Standard enthalpy change of solution n. 标准溶解焓变
The standard enthalpy change of solution is the enthalpy change when one mole of a solute dissolves in a solvent to give an infinitely dilute solution.
当 1 mol 溶剂溶解在水中形成一种稀释溶液时所放出的能量就是标准溶解焓变。
Standard enthalpy change of neutralization n.标准中和焓变
The standard enthalpy change of neutralization is the enthalpy change when one mol of H+ ions from an acid is completely neutralized by an alkali to give one mol of water.
标准中和焓变是酸中的氢离子被碱溶液完全中和形成1 mol 水。Standard enthalpy change of atomisation n. 标准原子化焓
The standard enthalpy change of atomization of an element is the enthalpy change when one mole of gaseous atoms is formed from one mole of the element in its standard state.
标准原子化焓是在标准条件下生成1摩尔气态原子的焓变。
Bond enthalpy n. 键能
Bond enthalpy is the energy needed to break a covalent bond ,and this indicates the strength of the bond .
键能是指破坏一个共价键所需要的能量，这能表明键的强度。
Hess’s law n. 盖斯定律
The total enthalpy change for a chemical reaction is independent of the route by which the reaction take place, provide the initial and final condition is the same.
如果反应前和反应后的条件完全相同，那总的焓变是相同的和反应路径无关。
chapter 6 electrochemistry
oxidation states n. 氧化态
oxidation states are usually calculated as the number of electrons that atoms lose, gain or share when they from ionic or covalent bonds in compounds.
氧化态通常通过计算他们形成共价化合物或离子化合物时失去，得到或公用电子的数目。
Redox n. 氧化还原反应
The term redox is used for the simultaneous processes of reduction and oxidation.
氧化还原反应就是用来描述氧化反应和还原反应同时进行的过程。
Electrolysis n 电解反应
When an electric current is passed through a solution of an ionic salt in water, the ions move through the solution and chemical reaction occur at the electrodes. This process is called electrolysis.
在离子化合物的水溶液中通电时，离子会通过水溶液在电极上发生化学反应。这个过程就是电解过程。
Anion n. 阳离子（anode 阳极）
Cations n. 阴离子（cathode 阴极）
The anions are attracted to the positively charged anode and the cations are attracted to the negatively charged cathode.
阳离子被吸引到阴极，阴离子被吸引到阳极。
Diaphragm cell n. 隔膜电池
In the diaphragm cell, a porous（多孔的）asbestos（石棉）diaphragm separate the anode compartment into the anode compartment.
在隔膜电池中，一个多孔的石棉隔膜把阳极室和阴极室隔开。
Chapter 7 equilibria
Equilibrium n. 化学平衡
It is dynamic at the molecular or ionic level. Both forward and reverse processes occur at equal rates. A closed system is required. Macroscopic properties remain constant.
化学平衡是在分子离子水平上的动态平衡，正反方向上的反应速率相同，需要在封闭体系中进行，宏观性质保持恒定。
Dynamic equilibrium n. 动态平衡
In general，in a dynamic equilibrium, the rate of reaction in the forwards direction equals the rate of reaction in the reverse direction.
通常在动态平衡中正反应速率等于逆反应速率。
Le Chatelier’s principle n. 夏特列原理
When any of the conditions affecting the position of a dynamic equilibrium are changed, then the position of that equilibrium will shift to minimize that change.
当外界条件影响动态平衡的方向时，平衡就会向减小这种影响的方向移动。
Equilibrium constant n. 平衡常数(Kc)
Equilibrium constant as the ratio of the product concentrations ( multiplied together ) divided by the reactant concentrations ( multiplied together ).
平衡常数是反应物浓度的乘积比上产物的乘积。
Chapter 8 reaction kinetics
Determining step n. 决定步骤
It is the slowest step in a mechanism which determines the overall rate of reaction. The slowest step in a reaction mechanism is called the determining step.
在化学反应中，反应最慢的一步决定反应的总速度，反应最慢的这步就成为反应的决定步。
Colorimeter n. 色度计
The colorimeter measures the amount of light of a specific colour that passes through a sample.
色度计用来测量穿过样品的特定颜色的光线数量。
Effective collision n. 有效碰撞
Effective collision occur when the kinetic energy of the colliding molecules provides sufficient energy for reaction.
当碰撞分子的动能提供了足够的反应能量时的碰撞称为有效碰撞。
Boltzmann distribution n. 波尔兹曼分布
The Boltzmann distribution represents the number of particles with particular energies.
波尔兹曼分布指的是有特定能量的分子的数目。
Activation energy n. 活化能
Molecules have to collide with a certain minimum energy Ea for there to be a chance of reaction. Ea is referred to as the activation energy.
分子碰撞发生化学反应所需要的最小的能量称为活化能。
Catalyst n. 催化剂
A catalyst is something added to a reaction that increase its rate, but dose not itself change in concentration, the same amount remains after the
reaction as before.
催化剂是用来加入反应中加快反应速度的，而催化剂本身不发生变化。
Enzyme n. 酶
Enzymes are proteins that act as biological catalysts.
酶是一种蛋白质生物催化剂。
Chapter 9 chemical periodicity
Covalent radius n. 共价半径
Covalent radius is half the distance between the nuclei of neighbouring atoms in molecules.
共价半径是分子中两个相邻原子距离的一半。
Metallic radius n. 金属半径
Metallic radius is half the distance between the nuclei of neighbouring atoms in metallic crystals.
金属半径是金属晶体中两个原子间距离的一般。
Atomic radius n. 原子半径
The covalent radius can be measured for most elements and is usually what is meant when we use the term atomic radius.