化學(xué)專業(yè)英語(yǔ)翻譯

1、精選優(yōu)質(zhì)文檔-傾情為你奉上02. THE NONMETAL ELEMENTSWe 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

2、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. 我們前面提到的。-非金屬表現(xiàn)出的性質(zhì)有很大的不同，這些金屬。作為一項(xiàng)規(guī)則，非金屬都是熱的不良導(dǎo)體電（石墨

3、碳是個(gè)例外）和熱；他們是脆的，往往是強(qiáng)烈的色彩，并顯示一個(gè)非常廣泛的熔點(diǎn)和沸點(diǎn)。其分子結(jié)構(gòu)，通常涉及一般共價(jià)鍵，從簡(jiǎn)單的雙原子分子氫，氯，碘，和氮?dú)獾拇蠓肿拥慕饎偸?，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

4、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非金屬，在室溫下是氣體的分子量和雙原子分子的惰性氣體，施加很小的分子間力。隨著分子量增大，我們遇到一個(gè)液體（溴）和固體（碘）的蒸氣壓力也表明小分子間力。某些性能的幾個(gè)非列于表2 Simple diatomic molecules are not formed by the heavier m

5、embers 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. T

6、he 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

7、 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.簡(jiǎn)單的雙原子分子沒(méi)有形成較重的群體成員的第五和第六在普通條件。這是在直

8、接對(duì)比的第一個(gè)成員的這些群體，氮?dú)夂脱鯕?。差異是因?yàn)檩^低的穩(wěn)定的債券形成軌道的第三個(gè)及以上的主要能量水平相對(duì)于第二主要能源。較大的原子半徑和更密集的電子云的第三周期元素和較高的不允許平行重疊的軌道需要一個(gè)強(qiáng)大的債券。這是一個(gè)普遍現(xiàn)象的債券形成的唯一的元素之間的二期。因此，氮元素和氧形成穩(wěn)定的分子與和債券，但其他成員的團(tuán)體形成更穩(wěn)定的結(jié)構(gòu)的基礎(chǔ)上債券只在普通條件。注3，第七族元素形成雙原子分子，但債券不需要飽和價(jià)。 Sulfur exhibits allotropic forms. Solid sulfur exists in two crystalline forms and in an am

9、orphous 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 S

10、8 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

11、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.硫展品同素異形體。固硫存在2晶體形式和非晶態(tài)形式。正交硫是通過(guò)結(jié)晶從一個(gè)合適的解決方案，如二硫化碳，它融化在112攝氏°單斜硫是由冷卻熔化的硫和它融化在119°C兩種形式的結(jié)晶硫磺熔化成s-gamma，由8分子。級(jí)分子折疊環(huán)和生存加熱至約160

12、6;C .160以上°，級(jí)環(huán)打開(kāi)，其中一些片段相互結(jié)合，形成高粘度混合物的不規(guī)則形線圈。在一系列的溫度較高的液體硫成為粘性，它不會(huì)從容器。顏色的變化也從稻草黃色硫的熔點(diǎn)為深褐色因?yàn)樗兊酶诱吵?。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

13、 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.

14、 In a few hours the amorphous sulfur reverts to small rhombic crystals and its rubbery property disappears.4沸點(diǎn)444°接近，large-coiled分子的硫部分退化和液體的粘度降低。如果把熱的液體硫到入冷水中淬火，產(chǎn)生無(wú)定形硫。無(wú)定形硫的結(jié)構(gòu)由八個(gè)硫原子的large-coiled螺旋與螺旋的每一圈；整體性描述一個(gè)無(wú)定形硫橡膠因?yàn)樗衿胀ㄏ鹉z。在幾個(gè)小時(shí)無(wú)定形硫還原為小菱形晶體和它的彈性也會(huì)消失。Sulfur, an important raw material in indu

15、strial 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

16、form or another, is used in large quantities for making sulfuric acid, fertilizers, insecticides, and paper.硫，一個(gè)重要的原材料工業(yè)化學(xué)，是自由的元素，如二氧化硫在火山地區(qū)，如硫化氫礦泉水，并在各種硫化礦如鐵黃鐵礦，閃鋅礦，方鉛礦等，并在共同形成石膏CaSO 42 H2O，硬石膏CaSO 4，和重晶石BaSO2 H2O。硫，一種或另一種形式，被大量用于制造硫酸，化肥，殺蟲(chóng)劑，和紙。Sulfur in the form of SO2 obtained in the roasting of

17、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 roasti

18、ng reaction involves the change:硫的形式，二氧化硫在焙燒硫化礦回收和轉(zhuǎn)化為硫酸，雖然以前這種二氧化硫被丟棄通過(guò)高大的煙囪。幸運(yùn)的是，現(xiàn)在是經(jīng)濟(jì)上有利的回收這些氣體，從而大大減少這種類型的大氣污染。一個(gè)典型的焙燒反應(yīng)涉及改變：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 electron

19、s 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 atoms (each atom

20、 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 air but, like

21、 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.磷，低于800由四原子分子，P。其分子結(jié)構(gòu)提供了一個(gè)共價(jià)鍵的三，可預(yù)期從三個(gè)未配對(duì)的電子的原子結(jié)構(gòu)，每個(gè)原子連接到三others6。而不是一個(gè)嚴(yán)格正交的方向，與三個(gè)債券90°對(duì)方，債券的角度只有60°。這種緊張的結(jié)構(gòu)是穩(wěn)定的相互交流的四個(gè)原子（每個(gè)原子保稅

22、其他三），但它是最活躍的形式磷化學(xué)。這種形式的磷，白色的修改，是在空氣中自燃。當(dāng)加熱到260攝氏°它變紅，磷，其結(jié)構(gòu)是模糊的。紅色磷在空氣中穩(wěn)定，如各種形式的磷，它應(yīng)該謹(jǐn)慎處理，因?yàn)樗内厔?shì)，遷移到骨頭，當(dāng)攝入，造成嚴(yán)重的生理?yè)p害。Elemental carbon 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 decr