1、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 n

2、eutrons 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.原子核內的質子數被稱為原子序數,或質子數，z。一個電中性原子的電子數量也等于原子序數，z。原子的總質量接近核內質子數和中子數之和。這個總數被稱為質量數a。中子在一個原子中的數量,中子數,給出了的數量為a-z。the term element refers to, a pure substance wi

3、th 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 gi

4、ven 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:單質是指,一個純物質由一種原子組成的?；瘜W家認為這種原子由它的原子數決定,因為它的性質決定了其化學行為。目前所有被知道的原子是z = 1 到z = 107的的原子，有107種化學元素。每一種化學元素被給以一個名字和一個獨特的符號。對于大多數元素符號都僅僅是英文名稱縮寫為一個

5、或兩個字母,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:一些元素,很久以前就被知道的,它們的符號根據他們的拉丁名字符號,例如:iron=fe(ferrum) copper=cu(cuprum) lead=pb(plumbum)鐵= =fe(ferrum) 銅= =cu(cuprum) 鉛= =pb(plu

6、mbum)a complete listing of the elements may be found in table 1.一個完整的元素表可以被發現于表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

7、 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 num

8、ber, 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 table。在十七世紀后期開始,在工作羅伯特

9、3;波以耳,提出當前公認的元素概念,大量的研究產生元素性質及其化合物的知識。在1869年,d.mendeleev和l. meyer,獨立工作,提出了周期性的律法。在現代形式,法律規定的元素的性質是原子序數的周期函數。換句話說,當元素的按原子序數增加列清單，有相近的特性的元素落在了明確的間隔在清單上有明確間隔。于是，將具有類似性質的元素排成縱列，從而把元素排成表格形式是可能的。這樣的安排被稱為一個周期表。each horizontal row of elements constitutes a period. it should be noted that the lengths of the

10、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 vert

11、ical 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.每個水平排的橫列元素構成

12、一個周期。但應該注意的是周期不同長度的。非常短的周期只包含兩種元素,后面跟著兩個短周期每個含8元素,然后兩個長周期每個由18個元素組成。下一個周期包含32元素,最后一個周期明顯不完整的。這樣的安排，元素在同一縱列有相似的特性。這些縱列構成化學家庭或組。為首的兩個8元素周期的成員被選定作為主族元素，其他組的成員被稱為過渡或內在過渡元素。in the periodic table, a heavy stepped line divides the elements into metals and nonmetals. elements to the left of this line (with

13、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 in

14、ner transition elements, are metals.在元素周期表中,沉重的階梯的線把元素分為金屬和非金屬元素。那條線的左邊(除氫)是金屬,而那些右邊是非金屬礦物等。這條線劃分只是為了方便。那些與分隔線相臨近的元素準金屬，既有金屬的性質，又有非金屬的性質?？梢钥闯觯蟛糠值脑?，是金屬元素。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

15、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

16、 1+ ions in many of their compounds. however, as is characteristic of most transition elements, they form ions having other charges as well.除了氫元素一種氣體元素外，a族的元素組成了堿金屬。它們是非?；顫姷慕饘伲鼈儚奈丛谧匀唤缰幸詥钨|狀態被發現。然而，它們的化合物是廣泛分布的。堿金屬的所有成員具有正一價的離子。與此相反，b族的元素銅、銀、和金相對來說是惰性的。它們和堿金屬的相似的，因為它們在化合物中以1+離子存在。但是和大多數過渡元素具有的特性一樣，它們

17、也能形成其它價的離子。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 elementszinc, cadmium, and mercury are less reactive than are

18、 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+.a族的元素就是通常所說的堿土金屬。它們離子的特征價是2+。這些金屬，尤其是族中最后兩個元素，幾乎和堿金屬一樣活潑。b 族元素，鋅、鎘、和汞比那些a的元素活性低，但比臨近的b族元素活潑。它們的特征價態也是2+。with the exception of boron, group iiia elements are also

19、 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+ ch

20、arge. group iiib consists of the metals scandium, yttrium, lanthanum, and actinium.除了硼以外，iiia元素相當活性金屬。鋁與空氣反應后是惰性的，但這一表現源于這一事實：在金屬表面形成了一個薄的，不可見的鋁的氧化膜，該膜保護大部分金屬不會被進一步氧化。a族金屬形成3+的離子。b族金屬由金屬鈧、釔、鑭和錒組成。group iva consists of a nonmetal, carbon, two metalloids, silicon and germanium, and two metals, tin and

21、 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

22、four other atoms; these compounds are nonelectrolytes when pure.第族有一個非金屬，碳，兩個準金屬硅和鍺，還有兩個金屬，錫和鉛組成。這些元素中每一個都形成一些化合物，這些化合物的分子式表明四個其他的原子出現在a族的原子周圍，例如四氯化碳，ccl4。b族金屬鈦、鋯和鉿，也形成每個b族原子與四個其他族原子結合的化合物，這些化合物純的時候是非電解質。the elements of group v a include three nonmetals nitrogen, phosphorus, and arsenicand two metal

23、s 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

24、variety of different compounds that their characteristics are not easily generalized.a族元素包含三個非金屬氮、磷、和砷，兩種金屬銻、鉍。盡管它們存在分子式為n2o5,pcl5,ascl5的化合物,但它們都不是離子型化合物。這些元素形成的化合物氮化物，磷化物，砷化物，其中離子的價態都是負3價。b族元素都是金屬，這些元素形成多種不同的化合物，它們的特點是不容易推廣的。with the exception of polonium, the elements of group via are typical nonm

25、etals. 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 fo

26、rmers. ” they are the most reactive nonmetals and are capable of reacting with practically all the metals and with most nonmetals, including each other.除了釙的元素以外，a族元素都是典型的非金屬。它們有時候被稱為硫族，來自希臘字，意思是“灰源體”。它們與金屬形成的二元化合物中以2-價的離子存在。a的元素都是非金屬，被稱為鹵素。來自希臘語,意即“鹽源體”。它們是最活潑的非金屬，并能夠與幾乎所有的金屬和非金屬包括它們自己反應。the element

27、s 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.b,b,viiib元素都是金屬。它們形成各種不同的化合物,在這一點上我們甚至不能舉出任何能表現各族元素典型變化的例子。the periodicity of chemical behav

28、ior 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 me

29、mber of the noble gas family.化學行為的周期性可以通過這樣的事實闡明。除了第一周期,每一個周期開始于一個非?；顫姷慕饘?。周期中的連續元素顯示，金屬性逐漸降低，最終成為非金屬。最后，在a,一個很活潑的非金屬元素。每一個周期以一個惰性氣體元素結束02非金屬元素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 elec

30、tricity (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

31、 the giant molecules of diamond, silicon and boron.我們早就注意到，非金屬呈現出來的性質與金屬有極大的不同。一般來說，非金屬是電和熱的不良導體（石墨碳是里例外）；他們是易碎的,有強烈的顏色,并表現出異常廣泛的融點和沸點。他們的分子結構,通常是包括了普通的共價鍵的變化,從簡單的雙原子分子的h2,，cl2,i2和n2到大分子的金剛石，硅和硼。the nonmetals that are gases at room temperature are the low-molecular weight diatomic molecules and the

32、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.低分子量的非金屬雙原子分子在室溫時是氣體，且分子間的作用力小。隨著分子量的增

33、大,我們遇到了液體(br2)和固體(i)，他們的蒸氣壓也表明分子間的作用力小。一些非金屬的確定的性質都列在表2。simple 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

34、 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 ge

35、neral 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

36、form diatomic molecules, but bonds are not required for saturation of valence.通常條件下，簡單的雙原子分子并不是由第五族和第六族相對更重的成員形成。這直接與這兩組的第一個成員,氮氣和氧氣形成對比。差別的出現時由于與第二主能級相反，第三和更高主能級的p軌道形成的鍵穩定性低。原子半徑更大和電子云密度更密集的第三和更高周期元素不允許軌道上良好的平行重疊對于強鍵是必須的。這是一個普遍的現象強鍵只有在第二周期元素間形成。因此,元素氮、氧由 和鍵形成穩定的分子,但它們組族的其他成員,形成穩定結構鍵只有在普通的條件才行。注意第七組

37、族元素形成雙原子分子,但鍵飽和度不做要求。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 m

38、elts 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 visc

39、ous 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硫表有同素異形體。固體硫以兩

40、結晶形式和一種無定形的形式存在。斜方硫是通過適當的溶液結晶得到的，如cs2,在112°c的融化。單斜硫是由冷卻熔化的硫形成，它的熔點是119°c。兩種結晶硫都熔化成s-gamma，由s8分子組成。s8的分子呈褶皺環狀耐高溫達160°c。超過160°c,s8環斷開,其中的一些片段相互結合形成一個高粘度的、形狀不規則的混合物。在較高的溫度范圍內，液態硫變得非常粘稠以至于不能從容器中倒出。顏色也從熔點是的稻草黃色變為深紅褐色，因為它變得更加粘稠。as4 the boiling point of 444 °c is approached, the la

41、rge-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

42、 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.接近沸點444°c時,大盤繞分子形狀的硫逐漸降解，并且液體硫粘度降低。如果把熱的液體硫倒冷水里驟冷

43、,就會產生無定形硫。無定形硫由八個硫原子組成大螺旋盤繞,自然界中一切無定形硫被描述為橡膠狀,是因為它像普通橡膠延伸。在幾小時無定形硫又還原成斜方的晶體硫，其橡膠性消失。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,

44、 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，工業化學的重要原料，像自由的元素那樣出現，如的火山區so2,礦泉水中的h2s、和各種各樣的硫礦石硫如黃鐵礦fes2如鐵、閃鋅礦zn

45、s,方鉛礦pbs等,共同形成的石膏caso42 h2o,硬石膏caso4,重晶石 baso42 h2o。硫，在一種或另一種形式,用于大量制造硫酸、肥料、殺蟲劑、和紙張。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. fortun

46、ately, it is now economically favorable to recover these gases, thus greatly reducing this type of atmospheric pollution. a typical roasting reaction involves the change:so2中的硫在硫化礦石焙燒中恢復和轉化為硫酸,盡管在過去幾年許多的二氧化硫通過特殊的高煙囪被摒棄。幸運的是,現在經濟有利用回收這些氣體,從而大幅度地減少這種大氣污染。一個典型的焙燒反應涉及改變:2 zns + 3 o22 zno + 2 so22 zns +

47、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 unpaired p electrons in its atomic structure, and each atom is attached to three others6. instead of a strictly orthogonal orientat

48、ion, 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 atoms (each atom is bonded to the other three), but it is chemically the most active form of phosphorus. this form of phosphorus

49、, 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 air but, like all forms of phosphorus, it should be handled carefully because of its tendency to migrate to the bones when in

50、gested, resulting in serious physiological damage.磷，800以下由四原子分子組成p4。其分子結構提供價三個共價鍵,可以從原子結構中三個未成對p電子的預計,每一個原子與另外三個相連。取代完全的正交方向,與三方彼此90°,鍵角為60°。據稱變形力結構是由四個穩定的原子相互作用,但是它是最活躍的磷形式。這種形式的磷、白色的變體,在空氣中自然。當加熱到260°c變為紅磷,其結構是不清楚的。紅色是在空氣中磷穩定，但是,就像所有形式的磷,它應該謹慎處理因攝入體內后會進入到骨頭,導致嚴重的生理傷害。elemental carbo

51、n exists in one of two crystalline structures diamond and graphite. the diamond structure, based on tetrahedral bonding of 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 th

52、e tetrahedral structure persists among the elements in this group carbon, silicon, germanium, and gray tin the interatomic 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 t

53、in is so soft that it exists in the form of microcrystals or merely as a powder. typical of the group iv diamond-type crystalline elements, it is a nonconductor and shows other nonmetallic properties7.元素碳以兩種晶體結構存在金剛石和石墨。金剛石結構基于四面體的sp3的雜化軌道結合，是在第四族元素中遇到的。我們可以猜想，隨著鍵長增加,金剛石晶形硬度降低。雖然四面體結構在這些元素中存在這個-碳、硅、

54、鍺,和灰錫-原子距離由碳的1.54提高到灰錫的2.80 a。因此。四大元素的鍵作用力范圍有非常強到相當薄弱。事實上,灰錫是柔軟的,它以微晶形式存在，或只是一種粉末。第四主族鉆石結晶型結晶元素的典型，他是一個絕緣體并顯示其它非金屬性質。06無機化合物的分類the classes of compoundsthousands and tens of thousands of compounds are known to the chemist today. it would be impossible to learn properties and behavior of even a fracti

55、on of this number if it had to be done on the basis of individual compounds1. fortunately, most chemical compounds can be grouped together in a few classes. then, if we can properly classify a compound . we are at once aware of the general properties of the compound from knowledge of the properties

56、of that class or group of compounds. for example. hcl is classed as an acid. and by becoming familiar with the behavior of acids as a distinct class, we are at once aware of the general properties of the compound2. a great many of the compounds we are to study may be classified as acids, bases, salt

57、s, metallic oxides, or nonmetallic oxides. of these five classes of compounds, the first three acids, bases, and salts are by far the most important3今天成千上萬種化合物已被化學家所知。如果根據個別化合物來了解這么多化合物的性質和行為，即使是其中一小部分也是不可能的。所幸的是，大多數化合物可以被歸為幾類。這樣，如果我們可以真確的對一個化合物進行分類。我們就可以根據這類化合物的性質知道這個化合物的一般性質。例如，hcl是一種酸，因為已經熟悉酸的性質，

58、我們就可以立即知道這一化合物的一般性質。我們學過的大多數化合物可以分為酸、堿、鹽、金屬氧化物、非金屬氧化物。這五類化合物，前三種酸、堿、鹽是最重要的。 when an acid, base, or salt is dissolved in water the resulting solution is a conductor of the electric current and is termed an electrolyte. if no conduction of current occurs, the compound is known as a nonelectrolyte.當一個酸

59、、堿、鹽溶于水中的溶液是一種電流的導體被稱為電解質。如果沒電流產生則該化合物被稱為非電解質。classification of common compounds常見的化合物分類by looking at the chemical formulas we may classify many common compounds in the following way.通過觀察化學公式中我們將許多普通化合物以如下方式分類。1. acids, in the conventional sense, may be recognized by noting that the h is written first in the formula and that the rest of the compound is generally nonmetallic. ex., hcl, h2so4, hclo.1。酸,用常規的感覺,會被注意到的h被寫在分