化學(xué)專(zhuān)業(yè)英語(yǔ)(修訂版)翻譯

1、01 THE ELEMENTS AND THE PERIODIC TABLE01 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 nearl

2、y 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. 在一個(gè)原子核中的質(zhì)子數(shù)量被稱(chēng)為原子序數(shù)，或質(zhì)子數(shù)，Z。在一個(gè)電中性原子中的電子數(shù)量也等于原子序數(shù)，Z。一個(gè)原子的總質(zhì)量被測(cè)定是非常接近于原子核中質(zhì)子和中子的總數(shù)。這個(gè)總數(shù)被稱(chēng)為質(zhì)量數(shù)，A。在一個(gè)原子中的中子數(shù)量等于A Z的數(shù)

3、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 che

4、mical 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: 這個(gè)術(shù)語(yǔ)(指chemical element)也可以指由相同質(zhì)子數(shù)的原子組成的純化學(xué)物質(zhì)。對(duì)化學(xué)家來(lái)說(shuō)，這類(lèi)原子通過(guò)原子數(shù)來(lái)說(shuō)明，因?yàn)樗男再|(zhì)是決定其化學(xué)行為。目前，從Z =

5、 1 到Z = 107的所有原子是知道的；有107種化學(xué)元素。每一種化學(xué)元素起了一個(gè)名字和獨(dú)特的象征。對(duì)于大多數(shù)元素都僅僅是一個(gè)象征的英文名稱(chēng)縮寫(xiě)形式，由一個(gè)或兩個(gè)字母組成，例如：oxygen=O nitrogen = N neon=Ne magnesium = Mg 氧= =O 氮 = = N氖= = Ne 鎂= =MgSome elements,which have been known for a long time,have symbols based on their Latin names, for example: 很久以來(lái)就已經(jīng)知道一些元素，根據(jù)他們的拉丁名字符號(hào)命名，例如：i

6、ron=Fe(ferrum) copper=Cu(cuprum) lead=Pb(plumbum) 鐵= =鐵(鐵) 銅= =銅(銅) 鉛= =鉛(鉛)A complete listing of the elements may be found in Table 1. 一個(gè)完整的元素可以在表1中被發(fā)現(xiàn)。Beginning in the late seventeenth century with the work of Robert Boyle, who proposed the presently accepted concept of an element, numerous invest

7、igations 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 ot

8、her 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 colu

9、mns2. Such an arrangement is called a periodic.早在十七世紀(jì)末期，羅伯特波義耳就開(kāi)始了這項(xiàng)工作，他提出了現(xiàn)在公認(rèn)的元素的概念，大量的研究使我們對(duì)元素及其化合物的性質(zhì)有了相當(dāng)?shù)牧私?。?869年，門(mén)捷列夫和邁耶，獨(dú)立工作，提出了元素周期律。用現(xiàn)代方式，元素周期律闡述了元素的特性原子序數(shù)的周期性函數(shù)。換句話說(shuō)，當(dāng)按原子序數(shù)增加的順序排列元素，具有相近特性的元素將沿著列表以一定的間隔下降。因此，將具有類(lèi)似性質(zhì)的元素排成縱列，從而把元素排成表格形式是有可能的。像這樣的排列叫元素周期表。Each horizontal row of elements cons

10、titutes 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

11、 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 ar

12、e called transition or inner transition elements. 每個(gè)水平排的元素構(gòu)成一個(gè)周期。但應(yīng)該注意的是，周期長(zhǎng)度會(huì)發(fā)生改變。非常短的周期只包含二元素，后面跟著兩個(gè)8個(gè)元素短周期，然后是兩個(gè)由18個(gè)元素組成的長(zhǎng)周期。下一個(gè)周期包括32個(gè)元素，最后一個(gè)周期明顯是不完整的。按照這樣的安排，在同一垂直欄的元素有相似的特點(diǎn)。這些垂直欄構(gòu)成化學(xué)族。兩個(gè)8個(gè)元素的周期組成的元素被認(rèn)為是主族元素，其他族的元素被稱(chēng)為過(guò)渡元素。In the periodic table, a heavy stepped line divides the elements into met

13、als 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 tha

14、t most of the elements, including all the transition and inner transition elements, are metals. 在元素周期表，階梯線將元素分成金屬和非金屬元素等。階梯線左邊的元素(除氫)是金屬，右邊的是非金屬元素等。這個(gè)分割僅為方便使用；元素分界線上的元素準(zhǔn)金屬具有金屬和非金屬的特性。這可以看出，大部分的元素，包括所有的過(guò)渡和內(nèi)在過(guò)渡元素，是金屬。Except for hydrogen, a gas, the elements of group IA make up the alkali metal family.

15、 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.

16、 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. 除了氫氣，IA由堿金屬元素組成。他們是非常活潑的金屬，在自然界中，它們從沒(méi)有以元素態(tài)形式出現(xiàn)。然而，他們的化合物是廣泛存在的。所有的堿金屬離子僅有1+的電荷。相比之下，IB 銅，銀和金是惰性的。在他

17、們的許多化合物他們存在1+離子，這與堿金屬離子是相似的。然而，像許多過(guò)渡元素所具有的特點(diǎn)一樣，他們也形成具有其他電荷的離子。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 elementszi

18、nc, 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+. IIA的元素被稱(chēng)為堿土金屬。其特點(diǎn)是離子電荷2+。這些金屬，特別是最后兩個(gè)元素，幾乎具有與堿金屬一樣的反應(yīng)活性。IIB元素，鋅，鎘，汞比IIA的元素具有更少的反應(yīng)活性，但是比相鄰的IB的元素有更強(qiáng)的反應(yīng)活性。IB的元素

19、離子的特征電荷也是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 meta

20、l 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、IIIA元素也是具有相當(dāng)強(qiáng)活性金屬。在空氣中鋁似乎惰性的，但這種行為的根源是金屬表面形成了一層薄的、不可見(jiàn)的氧化鋁膜，這層膜保護(hù)大量的金屬的進(jìn)一步氧化。IIIA金屬離子具有3+的電荷。IIIA由金屬鈧，釔，鑭系和錒系元素組成。Group IVA consists of a nonmet

21、al, 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, CCl4. The group IVB metals titanium, zirconium, and h

22、afnium also forms compounds in which each group IVB atom is combined with four other atoms; these compounds are nonelectrolytes when pure. IVA元素由一個(gè)非金屬，碳、兩個(gè)準(zhǔn)金屬，硅和鍺，和兩個(gè)金屬，錫和鉛組成。按照配位規(guī)則，這些元素的每一種形成一些化學(xué)物，這表明每一個(gè)IVA原子需要四個(gè)其他原子配位，例如，四氯化碳CCl4。IVB金屬鈦、鋯、和鉿也形成化合物，其中每個(gè)IVB原子結(jié)合四個(gè)其他原子；這些化合物的純物質(zhì)是非電解質(zhì)。The elements of g

23、roup 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 t

24、hree 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. VA元素包括三種非金屬-氮、磷、砷，和兩種金屬銻和鉍。盡管物質(zhì)N2O5，PCl5，AsCl5存在，但是其中沒(méi)有一個(gè)是離子。這些元素能形成化合物氮化物，磷化物，和砷化物其中離子帶3-價(jià)的負(fù)電荷。VB的元素都是金屬。這些元素形成各種不同的化合物，它們的特性不容易歸納。Wi

25、th 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

26、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. 除了釙的元素，VIA族元素是典型的非金屬。他們是眾所周知的硫族元素，這來(lái)自于希臘字母，詞意是“灰的創(chuàng)造者”。在他們與金屬離子形成的二元化合物中離子帶2

27、-價(jià)的電荷。A族的元素都是非金屬，被稱(chēng)為鹵素，來(lái)自希臘術(shù)語(yǔ)，意即“鹽的創(chuàng)造者”。他們是最具有反應(yīng)活性的非金屬，能夠與所有的金屬和大多數(shù)非金屬反應(yīng)，包括互相之間的反應(yīng)。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 group

28、s. B，B，和VIIIB族元素都是金屬。它們形成了各種各樣的化合物，在這一點(diǎn)上我們甚至不能舉出任何能表現(xiàn)各族元素典型變化的例子。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 becomin

29、g nonmetals, and finally, in group A, a very reactive nonmetal is found. Each period ends with a member of the noble gas family. 除了第一個(gè)周期，化學(xué)行為的周期性可以用事實(shí)說(shuō)明，每一個(gè)周期以一個(gè)非?；顫姷慕饘匍_(kāi)始。沿著周期元素顯示出了逐漸減少的金屬性，最終成為非金屬，最后，在A族，可以發(fā)現(xiàn)一個(gè)很活潑的非金屬元素。每一個(gè)周期的結(jié)尾是一個(gè)稀有氣體元素。02 THE NONMETAL ELEMENTS02非金屬元素We noted earlier that -nonmeta

30、ls 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 mol

31、ecular 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. 很早我們就已經(jīng)注意到非金屬表現(xiàn)出了與金屬不一樣的特性。一般來(lái)說(shuō)，非金屬是比較差的電子（石墨碳除外）和熱的導(dǎo)體；他們是易碎的，通常具有較強(qiáng)的顏色，并表現(xiàn)出很寬范圍的熔點(diǎn)和沸點(diǎn)。他們的分子結(jié)構(gòu)，通常是包括了普通的共價(jià)鍵，從簡(jiǎn)單的雙原子分子的H2，

32、Cl2，I2和N2到鉆石、硅和硼的大分子。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 s

33、mall intermolecular forces. Certain properties of a few nonmetals are listed in Table 2. 在室溫下是氣相的非金屬是低分子質(zhì)量的雙原子分子和施加了非常小的分子間作用力的稀有氣體。隨著分子量的增大，我們遇到了一個(gè)液體(Br2)和一個(gè)固體(I2)，其蒸氣壓也表明小的分子間作用力。一些非金屬的某些性質(zhì)列在表2中。Table 2 Molecular Weights and Melting Points of Certain NonmetalsDiatomic MoleculesMolecular WeightMelt

34、ing Point °CColorH22-239.1'NoneN228-210NoneF238-223Pale yellowO232-218Pale blueCl271-102Yellow greenBr2160-7.3Red brownI2254113GrayblackSimple 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

35、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 d

36、o 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 sta

37、ble 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. 通常情況下，V和VI族包括的更重的元素不能形成簡(jiǎn)單的雙原子分子。這與這兩個(gè)族中所包括的第一種元素是直接相反的，N2和O2。差別的出現(xiàn)是由于與第二主能級(jí)相反，第三和更高主能級(jí)的p軌道形成的鍵穩(wěn)定性較低。第三和更高周期元素的更大的原子半徑和更密的電子云不允許一個(gè)強(qiáng)的鍵

38、所必需的p軌道很好的平行重疊。這是一個(gè)普遍的現(xiàn)象強(qiáng)的鍵僅僅在第二周期的元素之間形成。因此，氮和氧元素形成了具有和鍵的穩(wěn)定分子，但是在通常情況下，這兩個(gè)族的其他元素可以形成僅僅基于鍵的更穩(wěn)定的結(jié)構(gòu)。需要注意的是第VII族元素形成了雙原子分子，但是鍵不需要用于價(jià)態(tài)的飽和。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

39、 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. Abo

40、ve 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

41、 yellow at sulfur's melting point to a deep reddish-brown as it becomes more viscous. 硫具有同素異形體。固態(tài)硫存在兩種晶形和一種無(wú)定形的形式。斜方硫通過(guò)在合適的溶液中結(jié)晶化獲得，如CS2，在112°C時(shí)融化。單斜硫通過(guò)冷卻融化的硫獲得和單斜硫在119°C時(shí)融化。兩種形式的晶體硫融化成S-gamma，它由S8分子組成。S8的分子起皺成環(huán)和加熱到160°C仍然存在。超過(guò)160°C， S8環(huán)被破壞，其中的一些片段相互結(jié)合形成一個(gè)高粘度的形狀不規(guī)則的混合物。在更高的溫度

42、范圍液態(tài)硫變得黏度很高，以致于在容器中不能倒出。隨著變得更粘稠，其顏色也從硫熔點(diǎn)時(shí)的稻草黃色變成紅褐色。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

43、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 sma

44、ll rhombic crystals and its rubbery property disappears. 隨著接近444°C的沸點(diǎn)，硫的大的螺旋狀分子被部分降解和液態(tài)硫的黏度降低。如果把熱的液態(tài)硫倒入到冷卻水里驟冷，就會(huì)產(chǎn)生無(wú)定形硫。無(wú)定形硫的結(jié)構(gòu)由具有8個(gè)硫原子的大的螺旋線組成；無(wú)定形硫的總特性被描述成是有彈性的，因?yàn)樗梢灶?lèi)似于普通的橡膠伸張。幾個(gè)小時(shí)之內(nèi)無(wú)定形硫恢復(fù)成菱形晶體，和它的彈性性質(zhì)消失。Sulfur, an important raw material in industrial chemistry, occurs as the free element, a

45、s 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 fo

46、r making sulfuric acid, fertilizers, insecticides, and paper. 硫在工業(yè)化學(xué)中是一種重要的原材料，它以單質(zhì)，在火山區(qū)域以SO2，在礦泉水中H2S，和各種硫化物出現(xiàn)，像黃鐵礦FeS2，閃鋅礦ZnS，方鉛礦PbS等等，還有石膏CaSO42H2O，硬石膏CaSO4，以及重晶石BaSO42H2O等普通形態(tài)。硫或以某種方式，用于大量制造硫酸、肥料、殺蟲(chóng)劑、和紙張。Sulfur in the form of SO2 obtained in the roasting of sulfide ores is recovered and converte

47、d 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: 2 ZnS

48、 + 3 O22 ZnO + 2 SO2在硫化物煅燒中獲得的以SO2形式存在的硫被轉(zhuǎn)化成硫酸，盡管在過(guò)去幾年許多二氧化硫通過(guò)高煙囪排放出去。幸運(yùn)的是，現(xiàn)在回收這些氣體的成本是較低的，從而這可以大幅度地減少大氣污染。典型的焙燒反應(yīng)如下：2 ZnS + 3 O2-2氧化鋅+ 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 unpair

49、ed p electrons in its atomic structure, and each atom is attached to three others6. Instead of a strictly orthogonal orientation, with the three bonds 90° to each other, the bond angles are only 60°. This supposedly strained structure is stabilized by the mutual interaction of the four ato

50、ms (each atom is bonded to the other three), but it is chemically the most active form of phosphorus. This form of phosphorus, the white modification, is spontaneously combustible in air. When heated to 260°C it changes to red phosphorus, whose structure is obscure. Red phosphorus is stable in

51、air but, like all forms of phosphorus, it should be handled carefully because of its tendency to migrate to the bones when ingested, resulting in serious physiological damage. 在低于800時(shí)，磷由四原子分子組成，P4。它的分子結(jié)構(gòu)提供了三個(gè)共價(jià)，可預(yù)期三個(gè)共價(jià)是由該原子結(jié)構(gòu)中三個(gè)未成對(duì)的p電子形成的，且每個(gè)原子都與另外三個(gè)相接。不是嚴(yán)格的正交取向，即三個(gè)鍵互成90°，而是鍵角僅僅是60°。這種可能的收

52、縮結(jié)構(gòu)通過(guò)4個(gè)原子的相互作用來(lái)穩(wěn)定（每一個(gè)原子與其他三個(gè)原子成鍵），但是它是化學(xué)上最活躍的磷的形式。這種形式的磷、白磷，在空氣中能自發(fā)燃燒。當(dāng)加熱到260°C時(shí)，它轉(zhuǎn)變成紅磷，其結(jié)構(gòu)是不確定的。紅色是在空氣中是穩(wěn)定的，但是，就像所有形式的磷，它應(yīng)該謹(jǐn)慎處理，因?yàn)楫?dāng)攝取時(shí)，它傾向于遷移到骨頭，這會(huì)導(dǎo)致嚴(yán)重的生理傷害。Elemental carbon exists in one of two crystalline structures diamond and graphite. The diamond structure, based on tetrahedral bonding of

53、 hybridized sp3 orbitals, is encountered among Group IV elements. We may expect that as the bond length increases, the hardness of the diamond-type crystal decreases. Although the tetrahedral structure persists among the elements in this group carbon, silicon, germanium, and gray tin the interatomic

54、 distances increase from 1.54 A for carbon to 2.80 A for gray tin. Consequently, the bond strengths among the four elements range from very strong to quite weak. In fact, gray tin is so soft that it exists in the form of microcrystals or merely as a powder. Typical of the Group IV diamond-type cryst

55、alline elements, it is a nonconductor and shows other nonmetallic properties7. 碳元素存在兩種晶體結(jié)構(gòu)金剛石和石墨?；陔s化的sp3軌道四面體成鍵的金剛石結(jié)構(gòu)遇到第IV族元素。我們可能希望鍵長(zhǎng)增加，金剛石類(lèi)型的晶體硬度降低。雖然四面體結(jié)構(gòu)的元素存在這個(gè)族-碳、硅、鍺，和灰錫-原子間的距離由碳的1.54Å增加到灰錫的2.80 Å。因此，在這四個(gè)元素之間，鍵的強(qiáng)度由強(qiáng)變?nèi)?。事?shí)上，灰錫是非常柔軟的，以致于它以微晶或粉末形式存在。碳作為典型的第IV族金剛石型晶體的元素，它是不良導(dǎo)體，且顯示其他非金屬性質(zhì)

56、。10 ALKANES10 烷烴Number of Isomers同分異構(gòu)體的數(shù)量The compounds now assigned the generic name alkane are also referred to as saturated hydrocarbons and as paraffin hydrocarbons. The word paraffin, from the Latin parum affinis(slight affinity)refers to the inert chemical nature of the substances and is applie

57、d also to the wax obtainable from petroleum and consisting of a mixture of higher alkanes.現(xiàn)在指定屬名為烷烴的化合物也被叫做飽和烷烴和鏈烷烴。石蠟一詞,來(lái)自拉丁語(yǔ)“parum affinis”(極少親和性的) ,指的是化學(xué)惰性的物質(zhì),并也適用于從石油和高級(jí)烷烴混合物中的得到的蠟。Derivation of the formulas of the pentanes (3 isomers), hexanes (5). and heptanes(9) has already demonstrated the s

58、harp rise in diversity with increasing carbon content.戊烷（3個(gè)同分異構(gòu)體），己烷（5個(gè)同分異構(gòu)體），和庚烷（9個(gè)同分異構(gòu)體）的衍生物已經(jīng)表明了隨著C含量增加，衍生物的數(shù)量會(huì)大幅度的上升。Normal Alkanes正烷烴Successive members of the series differ in composition by the increment CH2 and form a homologous series. Thus heptane and octane are homologous hydrocarbons; icosane is a higher homolog of methane.這一系列中接連相鄰的成員間組成不同，通過(guò)增加CH2形成同系物。因此，庚烷和辛烷是同系碳?xì)浠衔?；二十烷是甲烷的一個(gè)較高的同系物。Saturated Unbranched Chain Compounds and Univ