化学专业英语(修订版)翻译(50页).doc

-化学专业英语(修订版)翻译-第 49 页01 THE ELEMENTS AND THE PERIODIC TABLE 01 元素和元素周期表The number of protons in the nucleus of an atom is referred to as the atomic number, or proton number, Z. The number of electrons in an electrically neutral atom is also equal to the atomic number, Z. The total mass of an atom is determined very nearly by the total number of protons and neutrons in its nucleus. This total is called the mass number, A. The number of neutrons in an atom, the neutron number, is given by the quantity A-Z. 质子的数量在一个原子的核被称为原子序数,或质子数、周淑金、电子的数量在一个电中性原子也等于原子序数松山机场的总质量的原子做出很近的总数的质子和中子在它的核心。这个总数被称为大量胡逸舟、中子的数量在一个原子,中子数,给出了a - z的数量。The term element refers to, a pure substance with atoms all of a single kind. To the chemist the "kind" of atom is specified by its atomic number, since this is the property that determines its chemical behavior. At present all the atoms from Z = 1 to Z = 107 are known; there are 107 chemical elements. Each chemical element has been given a name and a distinctive symbol. For most elements the symbol is simply the abbreviated form of the English name consisting of one or two letters, for example: 这个术语是指元素,一个纯物质与原子组成一个单一的善良。在药房“客气”原子的原子数来确定它,因为它的性质是决定其化学行为。目前所有原子和Z = 1 a到Z = 107是知道的;有107种化学元素。每一种化学元素起了一个名字和独特的象征。对于大多数元素都仅仅是一个象征的英文名称缩写形式,一个或两个字母组成,例如:oxygen=O nitrogen = N neon=Ne magnesium = Mg 氮氧= = = = N霓虹灯啊= = = =不镁镁Some elements,which have been known for a long time,have symbols based on their Latin names, for example: 一些元素,长久以来,根据他们的拉丁名字符号,例如:iron=Fe(ferrum) copper=Cu(cuprum) lead=Pb(plumbum) 铁= =铁(铁)的铜= =铜(缓蚀剂)引线= =铅(铅)A complete listing of the elements may be found in Table 1. 一个完整的上市的元素可以被发现于表1。Beginning in the late seventeenth century with the work of Robert Boyle, who proposed the presently accepted concept of an element, numerous investigations produced a considerable knowledge of the properties of elements and their compounds1. In 1869, D.Mendeleev and L. Meyer, working independently, proposed the periodic law. In modern form, the law states that the properties of the elements are periodic functions of their atomic numbers. In other words, when the elements are listed in order of increasing atomic number, elements having closely similar properties will fall at definite intervals along the list. Thus it is possible to arrange the list of elements in tabular form with elements having similar properties placed in vertical columns2. Such an arrangement is called a periodic 在十七世纪后期开始的工作罗伯特·波以耳,提出当前一个元素的接受和运用的概念,产生了可观的知识大量调查的特性及其compounds1元素。在1869年,D.Mendeleev和l .迈耶,独立工作能力,提出了周期性的律法。在现代形式,法律规定的特性是周期函数的元素的原子编号。换句话说,当元素的顺序列出增加原子序数、元素有相近的财产落在了明确的间隔沿名单。由此,我们有可能安排的名单表格元素的元素有相似的性质columns2放置在垂直。这样的安排被称为一个周期Each horizontal row of elements constitutes a period. It should be noted that the lengths of the periods vary. There is a very short period containing only 2 elements, followed by two short periods of 8 elements each, and then two long periods of 18 elements each. The next period includes 32 elements, and the last period is apparently incomplete. With this arrangement, elements in the same vertical column have similar characteristics. These columns constitute the chemical families or groups. The groups headed by the members of the two 8-element periods are designated as main group elements, and the members of the other groups are called transition or inner transition elements. 每个水平排的元素构成一段时间。但应该注意的是,不同长度的时期。这是一个非常短只包含二元素,后面跟着两个短的每8元素,然后两个长期的18个元素组成。下一个阶段包括32元素,最后一期明显不完整的。这样的安排、元素在同一垂直柱有相似的特点。这些圆柱构成化学家庭或组。这个团体的成员为首的两8-element时期为主要集团指定的元素,其他组的成员被称为过渡或内在过渡元素。In the periodic table, a heavy stepped line divides the elements into metals and nonmetals. Elements to the left of this line (with the exception of hydrogen) are metals, while those to the right are nonmetals. This division is for convenience only; elements bordering the linethe metalloids-have properties characteristic of - both metals and nonmetals. It may be seen that most of the elements, including all the transition and inner transition elements, are metals. 在元素周期表,沉重的走线分元素到金属以及非金属矿物等。元素的左本线(除氢)是金属,而那些右边是非金属矿物等。这个师为方便使用,metalloids-have接壤的line-the元素的性质特点两者都是金属以及非金属矿物等。这可以被看见,大部分的元素,包括所有的过渡和内在过渡元素,是金属。Except for hydrogen, a gas, the elements of group IA make up the alkali metal family. They are very reactive metals, and they are never found in the elemental state in nature. However, their compounds are widespread. All the members of the alkali metal family, form ions having a charge of 1+ only. In contrast, the elements of group IB copper, silver, and goldare comparatively inert. They are similar to the alkali metals in that they exist as 1+ ions in many of their compounds. However, as is characteristic of most transition elements, they form ions having other charges as well. 除了氢气、气体、集团的元素是构成了碱金属的家庭。他们是非常活泼的金属,他们永远都不会被发现在国家自然元素。然而,他们的化合物是广泛的。所有成员的碱金属的家庭,形成离子有一个负责1 +而已。相比之下,IB -copper组元素,白银和gold-are较为活跃的。他们与碱性金属存在1 +离子在他们的许多化合物。然而,从大多数过渡元素的特征,它们形成离子有其它的费用。The elements of group IIA are known as the alkaline earth metals. Their characteristic ionic charge is 2+. These metals, particularly the last two members of the group, are almost as reactive as the alkali metals. The group IIB elementszinc, cadmium, and mercury are less reactive than are those of group II A5, but are more reactive than the neighboring elements of group IB. The characteristic charge on their ions is also 2+. 集团的元素IIA被称为碱性地球金属。其特点是离子电荷2 +。这些金属,特别是最后两队中成员的,几乎是作为反应碱性金属。集团elements-zinc IIB铅、镉、汞更少的反应比第二组A5,但是比较无功比相邻元素。特点集团建筑费用记在他们的离子也是2 +。With the exception of boron, group IIIA elements are also fairly reactive metals. Aluminum appears to be inert toward reaction with air, but this behavior stems from the fact that the metal forms a thin, invisible film of aluminum oxide on the surface, which protects the bulk of the metal from further oxidation. The metals of group IIIA form ions of 3+ charge. Group IIIB consists of the metals scandium, yttrium, lanthanum, and actinium. 除了硼、集团IIIA元素相当活性金属。铝似乎反应惰性向空气,但这种行为的根源是金属形成薄、隐形氧化铝膜的表面上,即保护大量的金属的进一步氧化。金属离子组的3 + IIIA形式的费用。由金属集团希望scandium、钇、稀土镧系,actinium。Group IVA consists of a nonmetal, carbon, two metalloids, silicon and germanium, and two metals, tin and lead. Each of these elements forms some compounds with formulas which indicate that four other atoms are present per group IVA atom, as, for example, carbon tetrachloride, GCl4. The group IVB metals titanium, zirconium, and hafnium also forms compounds in which each group IVB atom is combined with four other atoms; these compounds are nonelectrolytes when pure. 集团外语由一个非金属、碳、两个非金属等、硅和锗,和两个金属、锡、铅。这些要素的每一个物质形成一些计算公式表明,其他四个原子每组目前外语原子的,例如,四氯化碳GCl4。IVB金属集团-titanium、锆、hafnium化合物在那时间也形式每组IVB原子结合四个其他原子,这些化合物是nonelectrolytes纯。The elements of group V A include three nonmetals nitrogen, phosphorus, and arsenicand two metals antimony and bismuth. Although compounds with the formulas N2O5, PCl5, and AsCl5 exist, none of them is ionic. These elements do form compounds-nitrides, phosphides, and arsenides in which ions having charges of minus three occur. The elements of group VB are all metals. These elements form such a variety of different compounds that their characteristics are not easily generalized. 元素的一组包含三个非金属- V氮、磷、arsenic-and两种金属锑、铋。- - - - - - -虽然物质N2O5公式,PCl5,AsCl5存在,其中没有一个是离子。这些元素compounds-nitrides形式,phosphides,arsenides离子有指控减三发生。VB的元素都是金属集团。这些元素形态的各种不同的化合物,其特点是不易推广。With the exception of polonium, the elements of group VIA are typical nonmetals. They are sometimes known, as the, chalcogens, from the Greek word meaning "ash formers". In their binary compounds with metals they exist as ions having a charge of 2-. The elements of group A are all nonmetals and are known as the halogens. from the Greek term meaning "salt formers. ” They are the most reactive nonmetals and are capable of reacting with practically all the metals and with most nonmetals, including each other. 除了钋的元素组上通过是典型的非金属矿物等。他们有时是已知的,因为,chalcogens,从希腊单词意思是“灰的建设者”。在他们的二元化合物存在与金属离子有一个负责2 -。A的元素都是非金属和组被称为非卤素。从希腊术语,意即“盐成形机。“他们是最无功等,能够反应几乎所有的金属和大多数非金属,包括对方。The elements of groups B, B, and VIIIB are all metals. They form such a wide Variety of compounds that it is not practical at this point to present any examples as being typical of the behavior of the respective groups. 组织B的元素,B,VIIIB都是金属。它们形成这么多各种各样的化合物,它是不切合实际的在这一点上,以目前的典型实例的行为作为各自的组。The periodicity of chemical behavior is illustrated by the fact that. excluding the first period, each period begins with a very reactive metal. Successive element along the period show decreasing metallic character, eventually becoming nonmetals, and finally, in group A, a very reactive nonmetal is found. Each period ends with a member of the noble gas family. 化学行为的周期性的事实说明了。除了第一周期,每一个周期开始于一个非常活泼的金属。沿着周期连续元素显示减少金属而言,最终成为非金属,最后,在集团A,一个很活泼的非金属元素。每一个时期的结尾是一个惰性气体元素。02 THE NONMETAL ELEMENTS 02非金属元素We noted earlier. that -nonmetals exhibit properties that are greatly different from those of the metals. As a rule, the nonmetals are poor conductors of electricity (graphitic carbon is an exception) and heat; they are brittle, are often intensely colored, and show an unusually wide range of melting and boiling points. Their molecular structures, usually involving ordinary covalent bonds, vary from the simple diatomic molecules of H2, Cl2, I2, and N2 to the giant molecules of diamond, silicon and boron. 我们前面所指出的。-nonmetals展览财产,大大不同于其他的金属。作为一个规则,是电的不良导体非金属(石墨碳例外)和热量,他们是易碎的,通常是强烈的颜色,并表现出异常广泛的融化和沸点。他们的分子结构,通常是包括了普通的共价债券的变化,从简单的双原子分子的H2,含,i和N2期的大分子钻石、硅和硼。The nonmetals that are gases at room temperature are the low-molecular weight diatomic molecules and the noble gases that exert very small intermolecular forces. As the molecular weight increases, we encounter a liquid (Br2) and a solid (I2) whose vapor pressures also indicate small intermolecular forces. Certain properties of a few nonmetals are listed in Table 2. 气体的非金属,室温低分子物重量的双原子分子和高尚的气体时发挥非常小的力量。随着分子量的增大,我们遇到了一个液体(Br2)和一个固体(i)的蒸气压也表明小的电子的力量。一些非金属的某些性质都列在表2。Table 2- Molecular Weights and Melting Points of Certain Nonmetals 表2分子量和熔点的某些非金属矿物等Diatomic Molecules Molecular Weight Melting Point °C Color 双原子分子分子量的熔点°c的颜色H2 2 -239.1' None h2 2 -英尺没有N2 28 -210 None 28 -任何n2F2 38 -223 Pale yellow f2 38 -年-淡黄色O2 32 -218 Pale blue o2 32 - -浅蓝色Cl2 71 -102 Yellow green 71 -年-含黄色绿色Br2 160 -7.3 Red brown br2 160 -红-棕色I2 254 113 Grayblack 254 113 gray-black iSimple diatomic molecules are not formed by the heavier members of Groups V and VI at ordinary conditions. This is in direct contrast to the first members of these groups, N2 and O2. The difference arises because of the lower stability of bonds formed from p orbitals of the third and higher main energy levels as opposed to the second main energy level2. The larger atomic radii and more dense electron clouds of elements of the third period and higher do not allow good parallel overlap of p orbitals necessary for a strong bond. This is a general phenomenon strong bonds are formed only between elements of the second period. Thus, elemental nitrogen and oxygen form stable molecules with both and bonds, but other members of their groups form more stable structures based on bonds only at ordinary conditions. Note3 that Group VII elements form diatomic molecules, but bonds are not required for saturation of valence. 简单的双原子分子并未形成群体的成员由重五和六,在普通的条件。这直接对比这两组的第一个成员,氮气和氧气。差别产生因为较低的稳定的轨道上形成的债券p第三和更高的主要能量水平相对于level2第二大能源。较大的原子半径和电子云致密元素的三期和更高的不允许平行的轨道上重叠好必要的强p债券。这是一个普遍的现象是强壮债券只有元素之间形成的第二期。因此,元素氮、氧和形成稳定的分子和债券,但各自小组的其他成员,形成稳定结构基于债券只有在普通的条件。Note3那群七元素形成双原子分子,但债券饱和度不需要价。Sulfur exhibits allotropic forms. Solid sulfur exists in two crystalline forms and in an amorphous form. Rhombic sulfur is obtained by crystallization from a suitable solution, such as CS2, and it melts at 112°C. Monoclinic sulfur is formed by cooling melted sulfur and it melts at 119°C. Both forms of crystalline sulfur melt into S-gamma, which is composed of S8 molecules. The S8 molecules are puckered rings and survive heating to about 160°C. Above 160°C, the S8 rings break open, and some of these fragments combine with each other to form a highly viscous mixture of irregularly shaped coils. At a range of higher temperatures the liquid sulfur becomes so viscous that it will not pour from its container. The color also changes from straw yellow at sulfur's melting point to a deep reddish-brown as it becomes more viscous. allotropic硫展品形式。固硫存在于两水晶形式和一种无定形的形式。菱形硫得到结晶从适当的解决办法,如CS2,在112°C的融化。Monoclinic硫是由硫和融化冷却融化在119°C。两种形式的水晶融入S-gamma硫组成的S8的分子。S8的分子环和生存眯加热到160°C。超过160°C,破S8环,其中的一些片段相互结合形成一个高粘度的混合的形状不规则的线圈。在一系列的高温液体硫变得如此粘性,它将不可浇上从它的容器。从颜色变化也在硫的稻草黄色熔点到深红褐色也变得较粘稠。As4 the boiling point of 444 °C is approached, the large-coiled molecules of sulfur are partially degraded and the liquid sulfur decreases in viscosity. If the hot liquid sulfur is quenched by pouring it into cold water, the amorphous form of sulfur is produced. The structure of amorphous sulfur consists of large-coiled helices with eight sulfur atoms to each turn of the helix; the overall nature of amorphous sulfur is described as3 rubbery because it stretches much like ordinary rubber. In a few hours the amorphous sulfur reverts to small rhombic crystals and its rubbery property disappears. As4沸点444°C走近时,大硫分子部分分解和液体硫的粘度下降。如果把热的液体硫倒它熄灭跳进冰冷的水里,就会产生无定形硫。无定形硫的结构和八大螺旋状物的硫螺旋的每一次转身,总体性质描述的非晶态硫橡胶as3,因为它像普通橡胶延伸。在几小时无定形硫小菱形晶体和它的弹性性质就消失了。Sulfur, an important raw material in industrial chemistry, occurs as the free element, as SO2 in volcanic regions, as H2S in mineral waters, and in a variety of sulfide ores such as iron pyrite FeS2, zinc blende ZnS, galena PbS and such, and in common formations of gypsum CaSO4 2H2O, anhydrite CaSO4, and barytes BaSO4 2H2O. Sulfur, in one form or another, is used in large quantities for making sulfuric acid, fertilizers, insecticides, and paper. 硫、重要原料工业化学,发生在当自由的元素,因为中SO2的火山区,H2S矿泉水、和用各种各样的硫化矿石硫铁矿FeS2如铁、锌blende ZnS,PbS方铅矿等,共同形成的石膏CaSO42 H2O,CaSO4硬石膏,barytes BaSO42 H2O。硫、或另一种形式,用于大量制造硫酸、肥料、杀虫剂、和纸张。Sulfur in the form of SO2 obtained in the roasting of sulfide ores is recovered and converted to sulfuric acid, although in previous years much of this SO2 was discarded through exceptionally tall smokestacks. Fortunately, it is now economically favorable to recover these gases, thus greatly reducing this type of atmospheric pollution. A typical roasting reaction involves the change: 硫的形式获得焙烧的SO2在硫化矿石被恢复和转化为硫酸,尽管在过去几年许多这样的异常高二氧化硫被摒弃通过烟囱。幸运的是,现在经济有利的恢复这些气体,从而大幅度地减少这种污染大气。一个典型的焙烧反应涉及改变:2 ZnS + 3 O22 ZnO + 2 SO2 2 ZnS + 3 O2-2氧化锌+ 2二氧化硫Phosphorus, below 800 consists of tetratomic molecules, P4. Its molecular structure provides for a covalence of three, as may be expected from the three unpaired p electrons in its atomic structure, and each atom is attached to three others6. Instead of a strictly orthogonal orien