A-level化学词汇

来源：[本站编辑] 发布时间：2017-08-03 18:06:24 浏览217次

　　element n.元素
　　we all know materials can be broken down int【北京环球教育】o 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。
　　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
　　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。
　　ionization 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 ionization energy n.电离能
　　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。
　　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 ，thenumber 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  bond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）。考试时要把元素考试时要把元素考试时要把元素 ，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。
　　polarity 极性
　　Polarity is inherent in a magnet.
　　极性是磁铁的固有性质。
　　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。
　　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）。
　　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. 标准燃烧焓
　　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.
　　标准燃烧焓是指在标准状态下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 thisindicates 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。
　　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） diaphragmseparate 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。
　　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。
　　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。
　　Covalent radius n. 共价半径
　　Covalent radius is half the distance between the nuclei of neighbouringatoms 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 neighbouringatoms 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.
　　对于大多数元素的共价半径能通过测量得到，这也就是我们通常说的原子半径。
　　Siemens n. 西门子
　　Siemens are the reciprocal of the units of electrical resistance.
　　西门子是电阻的倒数。S=?-1
　　Conductivity n. 导电性
　　Conductivity values give an indication of how easily electrons move through the element.
　　导电性表示某种元素中电子的活动性。
　　Hard water n. 硬水
　　Hard water contains dissolved calcium ions.
　　硬水中含有钙离子。
　　Disproportionation n. 不均匀的，歧化反应
　　A particular type of redox reaction in which one species is oxidised and reduced at the same time.
　　一种特殊的氧化还原反应，一种物质被氧化，同时被还原 。
　　Strong acid n.强酸
　　Strong acid is fully dissociated to ions in aqueous solution.
　　在水溶液中完全电离的酸为强酸。
　　Weak acid n. 弱酸
　　Weak acid is the acid that their molecules are only partically ionized inaqueous solution.
　　弱酸是在水溶液中部分解离的酸。
　　Hydrocarbons n. 碳氢化合物
　　Compounds that contain only carbon and hydrogen atoms are known as hydrocarbons.
　　只含有碳原子和氢原子的化合物称为碳氢化合物。
　　Aromatic n. 芳香族的
　　Aromatic compounds n. 芳香族化合物
　　Aromatic compounds contain one or more arene rings. They are called aromatic compounds as they have distinctive , usually pleasant, smells.
　　芳香族化合物又一个或多个苯环，因为他们有使人愉悦的气味，而被称为芳香族化合物。
　　Aliphatic compounds n. 脂肪族化合物
　　All other compounds are aliphatic compounds except aromaticcompounds.
　　除了芳香族化合物其他的都是脂肪族化合物。
　　Molecular formula n. 分子式
　　A molecular formula simply shows the number of atoms of each element present in the molecular formula of hexane is C6H14。
　　分子式简单的表示了分子中各种原子的数目。
　　Structural formula n. 结构式
　　This shows how the atoms are joined together in a molecule. The structure formula of hexane is CH3CH2CH2CH2CH2CH3.
　　结构式表示的是原子如何结合在一起形成分子的。己烷的结构式是：CH3CH2CH2CH2CH2CH3.
　　General formula n. 通式
　　A general formula may be written for each series of compounds. For example, the general formula for the alkanes is CnH2n+2 (where n is the number of carbon atoms present).
　　通式用来表示同一系列的化合物，例如：烷烃的通式是 CnH2n+2（n表示碳原子的数目）
　　Displayed formula n. 展开式
　　This shows all the bonds and all the atoms. The displayed formula of hexane is: One of their disadvantages is that they are two-dimensional representation of mulecules which are three-dimensional.
　　展开式可以表示出所有的化学键和原子，例如己烷的展开式是：展开式有一个缺点是只能用二维空间分子表示三维空间的分子。
　　A three-dimensional formula  n. 三维空间式
　　A three-dimensional formula gives the best examples of the different types of formulae
　　三维结构式是表示分子空间结构的表示方式
　　Skeletal formula   n. 骨架式
　　This shows the carbon skeleton only. Hydrogen atoms on the carbon atoms are omitted. Carbon atoms are not labelled. Other types of atom are shown as in a structure formula. Skeletal formula are frequently used to show the structures of cyclic hydrocarbons. The skeletal foemula of hexane is:
　　骨架式只表示出碳骨架的存在，氢原子被忽略掉，碳原子也不被标识出来，但如果有其他原子就要表示出来，骨架式通常用来表示环状碳氢化合物，例如：己烷的骨架式是：
　　Homologous series n. 同系物
　　Homologous series is a series of compounds that contain the same functional group and that have the same general formula.
　　同系物是指具有相同官能团和相同的通式的化合物。
　　Substitution n. 取代反应
　　Substitution involves replacing an atom by another atom .
　　取代反应就是由一个原子取代另一分子中的一个原子。
　　Addition reaction n. 加成反应
　　Addition reactions involve two molecules joining together to form a single new molecule.
　　加成反应表示两个分子结合生成一个分子的过程。
　　Elimination n. 消去反应
　　Elimination involves the removal  of a molecule from a large one. The addition of ethene to steam may be reversed by passing ethonal vapour over a hot catalyst such as pumic. A water molecule is eliminated.
　　消去反应表示的是从一个大分子中移走一个小分子的过程。例如在乙醇中加入催化剂可以从乙醇中移走水分子。
　　Hydrolysis n. 水解反应
　　Hydrolysis reactions involve breaking covalent bonds by reaction withwater. The substitution of the bromine atom in bromoethane byhydrolysis is also a hydrolysis. The reaction proceeds much more slowlyin water.
　　CH3CH2Br(l) + H2O(l) → CH3CH2OH(aq) + HBr(aq)
　　水解反应是指和水反应断开一个共价键的过程
　　Catalysis n. 催化剂
　　Catalysts are frequently used in reactions to increase the rate of reaction. They do this by providing an alternative reaction pathway with a lower activation energy。
　　催化剂通常被用来加快反应速度，他们是通过提供一个需要更低反应活化能的路径来做到的。
　　heterolytic fission n. 异裂
　　When a covalent bond is broken to form two oppositely charged ions, the process is called heterolytic fission。
　　当一个共价键断裂形成两个电荷相反的离子，这个过程被称为异裂。
　　Electrophile n. 亲电试剂
　　An electrophile is an electron-pair acceptor which is attracted to an electron – rich molecule, leading to the formation of a new covalent bond between the electrophile and the molecule under attack.
　　亲电试剂是指电子对接受体，电子对接受体被吸引到富电子分子中能形成新的共价键。
　　Nucleophile n. 亲核试剂
　　A nucleophile is an electron-pair donor which is attracted to an atom with a partical positive charge, leading to the formation of a new covalent bond between the nucleophile and the atom under attack.
　　亲核试剂是指电子对贡献体，电子对贡献体会被吸引到带有部分正电荷的原子中形成新的共价键。