1、1.Practically all substance expand when heated and contract when cooled. 实际上一切物质都是热胀冷缩的。 (省译 “ when, and, when”) 2.Organic compounds are usually volatile and possess low melting points. 有机化合物通常容易挥发且熔点较低。 (省译动词 “ possess”) 3.Being stable in air at ordinary temperature ,mercury combines with oxygen if
2、 heated.水银常温下在空气中是稳定的，但如果加热时，它会与氧化合。 1.Tertiary alcohols are very resistant to oxidation. 叔醇难于氧化 2.For the series of normal alkanes, those having one to four carbon atoms are gases. 对直链烃系而言，含有一至四个碳原子的是气体。 1.If the unsaturation is due to the presence of a triple bond then the compounds are called alk
3、ynes. 如果不饱和现象是由于叁键的存在，则该 类化合物称为炔烃。 2. . A body with a negative charge possesses more elections than protons. 带 负电 的 物体 所含的电子比质子多。 (不译作“一个负电，一个物体” ) 1. The zinc plate becomes more and more negatively charged with electrons ,as more atoms of zinc dissolve. 随着越来越多的锌原子溶解，锌极板上充满了电子，使它变得越来越负。 2. Gases dif
4、fer from solids in that the former have greater compressibility than the latter. 气体和固体的区别在于前者比后者有更大的压缩性。 (v.n.) 3. One of the outstanding properties of carbon atom is its ability to share its electrons with other carbon atoms. 碳原子的突出性质之一是它能与其它碳原子共用其电子。 (n.v.) 4. The chlorine from salt is used for bl
5、eaching paper and textiles. 用食盐制取的氯被用来漂白纸张和纺织品。 (prep.v.) 5. In their work they pay much attention to the combination of theory with practice. 他们在工作中非常注重理论联系实际。 (n.v.) 1.In an absorption system, the refrigerant is usually ammonia. 吸收系统中，通常用氨做冷却剂 。 (表语 宾语 ) 2.Organic compounds will not usually conduc
6、t an electric current when in solution. 有机化合物的溶液通常不导电。 (状语 主语 ) 3.The two electrons involved in a covalent bond have their spins oppositely directed. 此共价键中的两个电子的自旋方向相反。 (宾语 主语 ) 4.None of these metals have conductivity higher than copper. 这些金属的导电率都不会超过铜。 (宾语 主语 ) 5.The different hydrocarbons in crud
7、e oil boil at different temperatures. 原油中各种烃的沸点不同。 (谓语 主语 ) 1. Wetting agents are required to prepare proper dispersion of fine particle powders in liquids/pastes such as color makeup. 要制备将细小粉粒适当分散在液体或膏体中的产品，如着色化妆品，需要润湿剂。 2. Alkanes undergo reactions such as cracking, alkylation, oxidation, halogena
8、tion, nitration and so on. 烷烃能进行诸如 裂化、烷基化、氧化、卤化、硝化等反应。 (同位语的变序 ) 1 Large-scale evaporation process is being developed and used for recovering potable water from seawater. Here the condensed water is the desired product. Only a fraction of the total water in the feed is recovered , and the remainder
9、is discarded. 目前，大规模的蒸发工艺过程正在发展并用于从海水中回收有饮用水。这里 ,冷凝水就是希望得到的产品。但被回收的的水仅是加入的总水量的一部分 ,而剩余部分则被扔掉。 2 If the product is suspected of being a compound already known, it is then physically compared with the known material to establish its identity. 如果推测产物是一个已知的化合物 ,那就可以用物理方法将它与已知物进行比较以确定它们的一致性。 3 Careful at
10、tention must be paid to the construction of the diagram in using this equation. 用这一公式时必须认真注意其图形结构。 1.The objective of evaporation is to concentrate a solution consisting of a nonvolatile solute and a volatile solvent. 蒸发的目的是浓缩由非挥发性溶质和挥发性溶剂所组成的溶液。 (现在分词短语作后置定语，修饰“ solution” ，译作 “ 的 ” 。 ) 2.This led t
11、o the proposals that an acid is a chemical species that can give hydrogen ions or protons in a chemical reaction. 这就导致这样一个提法：酸是一类化学物质， 它在化学反应中能给出氢离子或质子。 (定语从句译成并列分句 ) 3.Potential energy that is not so obvious as kinetic energy exists in many things. 势能虽然不象动能那样明显，但它存在于许多物体之中。 (定语从句译成让步状语从句 ) 4.A gas
12、occupies all of any container in which it is placed. 无论把气体装在什么容器里，都会把它充满。 (定语从句译成条件状语从句 ) 5.The problem whether natural rubber is a polymer with linear chain molecules has been solved. 天然橡胶是否是线型链状分子的聚合物，这个问题已经解决了。 (同位语作后置定语，其先行词为“ problem”，翻译时要变序 ) 6.Metal , which possess strength, ductility, mallea
13、bility, and other remarkable properties, have suppleanted other classes of engineering materials to a considerable extent. 由于金属所具有的强度、延展性、柔韧性以及其它显著特性，因而在很大程度上已替代了其它种类的工程材料。 (定语从句译成原因状语从句 ) 7.Matter has certain features or properties that enable us to recognize it easily 物质具有一定的特征或特性，所以我们能够容易地识别它。 1
14、Total determination of structure is also possible by means of X-ray diffraction, so that the classical goal of structure studies-ascertaining the relative spatial positions of all the atoms in any molecule-can be readily and routinely attained. 全面的结构测定也可 以借助 X 射线衍射来完成，因此结构研究的经典目标 确定任何分子中所有原子的相对空间位置
15、就能很快地用常规的方法来完成。 2 Valuable solvent vapors carried by a gas stream may be recovered for reuse by washing the gas with an appropriate solvent for the vapors. 被气流携带的有价值的溶剂蒸汽可用下法回收再用，即用适合于该蒸汽的溶剂洗涤该气流。 3 The idea that the four valence bonds of the carbon atom are directed toward the corners of a regular
16、tetrahedron was advanced in 1874 by Vant Hoff and independently by Le Bel to explain the existence of right-handed and left-handed forms of some organic compounds, which shows in the face development of crystals(enantiomorphism) and in the power of solutions to rotate the plane of polarization of a
17、transmitted beam of polarized light either to the right to the left (optical activity). 碳原子的四个价键都指向正四面体的四角这一概念，是 1874 年由范托夫和赖贝尔各自分别提出的，以解释某些有机化合物的右旋体或左旋体的存在，它们的存在表现在晶面的发展 (对映形态 )和溶液把透入的偏振光束的偏振面向右或向左旋转的能力 (旋光性 )上。 (同位语从句采用倒译法，详见 6.3 ；定语从句译成并列分句详见 8.4 二。 ) 4.This procedure eliminates errors caused by
18、the presence of several drops of the substance which may adhere to the sides and tip of the pipette. After this manipulation ,more alcohol is added until a clear solution is obtained. 这样能消除由附着在管壁或管尖的样品所带来的误差。然后再加入乙醇，直至澄清。 5.A second method which is the least accurate is very often used in the indust
19、ry because of its great ease and convenience. 第二种配制方法准确性最初差，但是，由于操作简单在工业上经常采用。 6.Since the alcohol ordinarily available is the commercial 95 per cent by volume alcohol, this product is used in preparing alcohol of various strengths. 既然通常所用的商业乙醇的浓度为 95%（体积比），因此我们可用该浓度的乙醇来制备各种浓度的乙醇液。 7.In reporting th
20、e optical rotation of a substance ,one usually writes:optical Rotation at 20 C+1920 or in abbreviated form +19 20 ,meaning that the rotation taken at 20 , using sodium light (D line) is found to be plus 19 degree and 20 minutes. 在报道某物质的旋光度时，我们习 惯按下列的写法。如某物质在 20 C，旋光度为 +1920； 或简写为 ，+19 20；即表示，在 20C 时
21、，用钠光测定的旋光度为正 19 度 20 分。 8.When the cause for the fragrance breakdown is found to lie not in a principal component of the product, but in an impurity or gradually developing breakdown product(e.g., rancidity of unsaturated fatty acids and hydrogen chloride from propellant( ),it is best to change the
22、product formulation rather than the fragrancethe impurities or breakdown products usually have other undesirable effects in addition to that on the fragrance. 如果发现香料的分解不是出于产品的一个主要成分，而是一种杂质或是一种逐渐产生的分解产物（如不饱和脂肪酸的变质和推进剂 2 产生的氯化氢），则最好改变产品的配方而不是改变香料的配制，因为这种杂质或分解产物除了对香料产生作用外，通常还会有其他不良的影响。 9.In contrast, c
23、ross-linked polymers usually lack the ability to be completely dissolved by solvents, and usually do not undergoing melting or fusion. 相反，交联聚合物通常缺乏被溶剂完全溶解的能力，而且经常不能熔化或熔融。 10.Similarly, the order with respect to B can be determined by plotting logA,0 against logB0 with A0 held constant. 类似地， B 的级数可由在
24、 A0 恒定时用 logA,0 对 logB0 作曲线而得到。 11.Whereas this is approximately so, over limited ranges of temperature difference for which U is nearly constant ,in practice U may well be influenced both by the temperature difference and by the absolute value of the temperatures. 其实在一个有限的温差范围内当 U 几乎恒定时，是近似如此；但实际上
25、U 却可能受温差和绝对温度二者的影响很大。 12.If it is required to know the area needed for the transfer of heat at a specified rate, the temperature difference T, and the value of the overall heat transfer coefficient in any design problem in which heating or cooling is involved. 若需知道在一指定速率下进行传热所需的面积时，就须知道包括加热或冷却在内的设计问
26、题中的温差T 及总传热系数值。 13.Additionally, the respective isomer distribution in the individual surfactant classes has great significance, because from it, varying application properties do result. 此外，有关的异构体在各类表面活性剂中的分布也可具有重要作用 ，因为不同的分布确实可以产生不相同的应用性能。 14.A mixture of 1750 g. of crystalline sodium sulfite(Na2S
27、O37H2O),625 g.of sodium bicarbonate and 5 liters of water was agitated at room temperature for about two hours, or until the solid carbonate had disappeared .The solution was then cooled by means of an ice-bath to 5 - 10 and 500 g.of commercial citral added with vigorous agitation, which was continu
28、ed for three to four hours ,intimate contact being effected between oil and solution, and air excluded as much as possible. Under these conditions ,only the citral went into solution, namely, as the labile dihydrodisulfonic acid derivative. The solution was agitated thoroughly with about 500 cc. of
29、ether, the ether removed and the process repeated in order to remove all undissolved impurities. 在室温下将 1750 克晶状亚硫酸钠， 625 克碳酸氢钠及 5L 水混合并搅拌两小时，或搅拌至固体碳酸盐消失。然后用冰水浴将温度降至 5 - 10， 加入 500 克市售柠檬醛剧烈搅拌，并持续三、四小时以使油与溶液充分接触，同时尽可能的排除空气。在这些条件下，只有柠檬醛进入溶液，即柠檬醛形成不稳定的二氢 -二磺酸衍生物。将溶液与 500c.c.乙醚充分搅拌，除去乙醚，如此重复数次以除去所有不能溶解的杂
30、质。 1.The size of atoms decreases from left ot right across a period in the periodic table 在元素周期表中沿着周期从左到右的半径递减 2.On descending a group in the periodic table such as lithium,sodium,potassium,rubidium,caesium,the size of the atoms increases due to the effect of extra shells of electrons being added;th
31、is outweighs the effect of increased nuclear charge. 在周期表中同族从上到下例如锂、钠、钾、铷和铯，由于增加额外电子层的影响，原子的半径递减，这个影响超过增加核电荷所起的作用。 3.Thus the effective nuclear charge is increased and the electrons are pulled in. 这样就使有效核电荷增加，从而将电子拉向原子核 1.The most electropositive elements are found in the lower left of the periodic
32、table and the most nonmetallic in the top right. 电正性最强的元素出现在周期表的左下角，而非金属性最强的元素则出现在周期表的右上角 2.Electropositivity is really the converse of electronegativity,but it is convenient to retain the concept of electropositivity when describing metals. 电正性实际上是电负性的相反概念，但在描述金属的时，保留电正性概念较为方便。 3.However,this gener
33、alization does not hold for the d block,and particularly for the central groups of transition elements (Cr,Mn,Fe,Co,Ni) where basicity and the ability to form simple ions decreases on descending the group. 不过这个规律不适用与 d 区 (元素 )，特别不适用于中间组的过度元素 (Cr,Mn,Fe,Co,Ni),(因为它们的 )碱性和生成简单离子的能力在族中 (自上而下 )递降。 1.Sinc
34、e the zinc reaction in the forward reaction produces a larger negative potential, 由于锌的正向反应产生较大 的负电势， 2.Similar applications in which one metal is sacrificed to protect another are the attaching of sacrificial blocks of magnesium to underground steel pipelines and the hulls of ships to prevent the ru
35、sting of iron. 牺牲一种金属以保护另一种金属的类似应用是把一块作牺牲用的镁锭同下部的钢管和船体连接起来以防止铁的生锈。 3.Standard electrode potentials are measured on a scale with: 标准电极电势是以 (如下 )标度 (为准 )来测量的 4.Whenever this is found,the species in the middle (Cu+ in this case) disproportionates,that is it behaves as both a self-oxidizing and a self-r
36、educing agent because it is energetically favourable for the following two changes to occur together. 当存在这种情况时，处于中间的物质 (本例中的 Cu+)便会发生歧化反应，即它起自身氧化剂和自身还原剂的作用，因为下列两种变化同时发生在能量上是有利的。 1.It is an historically important molecule,and as a probable constituent of the primeval broth it may have been a building
37、 block from which such molecules as morphine and peptides were constructed. 它是具有历史意义的重要分子，因为它是原始肉汤的一种可能成分，或许还是构成吗啡和肽这样的分子的结构单元。 2.Of course,it isnt,for methane is a three-dimensional molecule with tetrahedral symmetry,and the distance between all the hydrogens is exactly the same. (而事实上 )当然不是 (这种情况
38、)，因为甲烷是一个四面体对称的三维分子，因此所有氢原子之间的距离都是完全相等的。 3.If a frameworkmodel of ethane is inspected,it is apparent that there are an infinite number of orientationgs which the two CH3 groups can take with respect to each other. 如果我们观察一下乙烷的骨架模型，就不难看出两个甲基的相对定向的数量是无线的。 4.This structure can be represented by a “three
39、-quarters view” or by a “head-on view”,in which the viewer looks directly down the axis of the carbon-carbon bond(often referred to Newman projection). 这一结构可用“ 3/4 透视图”或“正视图”来表示，后者是观察者直接通过碳 -碳键的轴向后看 5.A more subtle kind of isomerism is illustrated by the eclipsed and staggered ofrms of ethane. 根据乙 烷
40、的重叠式和交叉式，还可描述一种更细微的异构现象。 6.There is , in other words , rapid rotation around the CC bond,and for most purposes ethane can be considered as a rapidly equilibrating mixture of molecules in the eclipsed and staggered conformations along with the infinite number of additional conformations falling betwe
41、en the extremes. 换句话说，围绕 C-C 键旋转的速度很快，并且在大多数情况下，乙烷都可看做是，在重叠构象和交叉构象，以及在这两个极端构象之间的无数其它构象中迅速平衡的分子混合物。 1.Thus, certain carbon nucleophiles add so efficiently that for all practical purposes , the reactions are irreversible , whereas halogen nucleophiles add so inefficiently that , for all practical purp
42、ose , the reactions dont proceed at all. 因此，某些碳亲核试剂的加成效率非常高，以致反应实际上是不可逆的，而卤素亲核试剂的加成效率却很低，实际上反应完全不能进行。 2.Reactions of this type provide useful intermediates in synthesis sequences and the reader who takes itme out at this point to consider the ramifications that are possible with various combinations
43、 o faldehydes, ketones, and carbon nucleophiles is ready to play the game of “paper synthesis”. 这种类型的反应提供了合成程序中的有用的中间体，读者在这方面只要花些时间考虑醛、酮和亲核试剂的各种可能的化合所出现的结果，就易于玩一场“纸上合成”的游戏。 3.These characterisitcs make “derivatives” of this sort valuable,for they are pure compounds that have retained the carbon fram
44、ework of the original aldehyde or ketone, possess melting points which can be compared with those of known compounds and can be converted back to the original aldehyde or ketone by hydrolysis. 这些纯净物具有下列特点：保留原来的醛和酮的碳架，所具有的熔点可以与那些已知化合物的熔点进行比较，并且通过水解能转变为原来的醛和酮，因此这些特点使得这类“衍生物”具有重要价值。 1.As the relative m
45、olecular mass increases, volatility decreases and the esters gradually become viscous, oily liquids or waxy solids. 随着相对分子质量的增加，其挥发性降低，酯逐渐变粘而成油状液体或蜡状固体。 2.The composition of the equilibrium mixture is the same, no matter whether one has started from an equimolar mixture of acid and alcohol, or ester
46、 and water. 起始的等摩尔混合物无论是羧酸和醇还是酯和水，平衡混合物的组成都是相同的 3.Esters are reduced by lithium tetrahydridoaluminate to primary alcohols corresponding to the acid from which the ester is derived. 酯被氢化锂铝还原为相应于形成酯的羧酸的 伯醇。 4.The reaction of an acid chloride with an amine is used commercially in the manufacture of the
47、 very important range of semi-synthetic penicillins, first produced by The Beecham Group in 1959. 酰氯与胺的反应在商业上用来制造具有重要地位的半合成青霉素，它首先由贝克曼小组于 1959 年制备。 1.Even though it is not all unusual to find synthetic polymer having relative average molecular weights greater than 1,000,000 and naturally occurring s
48、ubstances such as rubber, cellulose, and the proteins,as well as certain synthetic materials, already well known, were considered macromolecules. 虽然，发现平均相对分子质量大于 1,000,000 的合成聚合物和相对分子质量为几百万的天然聚合物并非稀罕之事，但是直到 1920-1930 的年的中期，天然存在的物质如橡胶、纤维和蛋白质以及某些众所周知的合成物质，才被认为是大分子。 2.It is not appropriate in this limi
49、ted discussion to introduce the interesting argument, both pro and con, which finally led to the acceptance of the macromolecular hypothesis; however,it should be stated that the brilliant work of Nobel Laureate Dr. Hermann Staudinger played an overwhelming role in its final acceptance. 在这个有限的讨论中，从正反两方面介绍有趣的争论是不适合的，这些争论最后都 导致接受大分子的假说；但是必须指出，诺贝尔资金获得者 H施陶丁格博士 (Dr.Hermann Staudinger)的辉煌成就，对最后接受这个假说，起了决定性的作用。 3.Although the above date marks the beginning of t
