第十三章p区元素（二）.ppt

1、2018/10/7,刘晓瑭,1,无机化学,2010级应用化学专业刘晓瑭E-mail：Tel： 85280325Blog：http:/ 氧族元素Oxygen Family Elements,2018/10/7,刘晓瑭,3,目 录,9.1氧族元素的通性9.2 氧9.3 硫和硫化物9.4硫的含氧化合物9.5硒和碲,硫的成键特征 S：3s23p43d0 1 离子键：如Na2S、CaS、(NH4)2S等。 2 共价键： (1) 共价单键，H2S、SCl2 ； (2) 共价双键，CS2； (3) 3d成键，SOCl2、SF4、SO3、SF6等。 3 多硫链：Sn 长硫链。 过硫化物Na2S2、FeS2、H

2、2S2、S2Cl2，多硫化氢H2Sn (硫烷)、多硫化物MSn和连多硫酸H2SnO6。,硫原子和氧原子成键特征的异同点,离子键 共价单键 重键 配位键O原子： O2- -O- O= OO OS原子： S2- -S- S= S,形成离子键的能力较弱,主要形成共价单键,形成重键的能力较弱,可以给出电子对形成配键,硫原子半径较大，变形性大，以共价单键为主要成键特征。它的另一个成键特点是S原子间可以形成硫链：-S-S-S-S-,2018/10/7,刘晓瑭,6,9.3 硫和硫化物,9.3.1 单质硫9.3.2硫化氢和氢硫酸9.3.3硫化物,2018/10/7,刘晓瑭,7,1.单质硫的存在,在自然界中存在

3、天然单质的硫，主要在火山区，这是因为 2H2S + SO2 = 3S + 2H2O 2H2S + O2 = 2S + 2H2O 反应物中的H2S来自地下硫化物矿床与高温水蒸汽的反应。,单斜硫,斜方硫,弹性硫,升华硫,2 单质硫的结构,S以sp3杂化形成环状S8分子,(1) S8：最稳定的形式，成环状或皇冠状。 它有两种形式： 斜方硫(orthorhombic) 呈黄色； 单斜硫（nonoclinic）呈浅黄色。 (2) 同素异形体的转化 S2是顺磁性的，而S4 , S6 , S8 都是反磁性的,2018/10/7,刘晓瑭,9,Charles Goodyear Charles Goodyear

4、(1800-1860), American inventor, experimented with, perfected, and promoted the use of vulcanized rubber. He was instrumental in establishing the rubber industry in the United States.Charles Goodyear was born on Dec. 29, 1800, in New Haven, Conn. He attended the local public schools. His father was a

5、n inventor, manufacturer, and merchant of hardware, especially of farm tools. When Charles was 17, his father sent him to Philadelphia to learn the business, and at 21 he returned to become his fathers partner. He married at the age of 24 and 2 years later opened a store in Philadelphia. In 1830 a l

6、ifetime of financial distress began for the Goodyears when both father and son went bankrupt.On a trip to New York City that year, Goodyear visited a store that sold goods made of india rubber, a product only recently manufactured in America. Inspired by the possibilities of the material, he determi

7、ned to improve its usefulness. His first experiments were carried out in jail, where he had been sent for failure to pay his debts.In 1837 Goodyear settled his family on the charity of friends near New Haven and went to New York to continue his work. He received a patent for an improved type of rubb

8、er and was able to find a modest amount of financial backing. After moving to Massachusetts, he met Nathaniel M. Hayward, an inventor, whose patent on a process for mixing sulfur with rubber he bought. Goodyear intended to combine the new patented process with his old one, which involved coating rub

9、ber with an acid and metal.During an argument one day in his shop, Goodyear accidentally dropped a piece of the sulfur-impregnated rubber on a hot stove. Instead of melting, it merely charred slightly. Realizing the importance of this (two major drawbacks to using rubber were that it melted at high

10、temperatures and tended to harden at low temperatures), he began experiments to discover the proper proportions and method of baking the new type of rubber, which he called vulcanized. His critical patent was issued on June 15, 1844, after he had borrowed $50,000 for experiments, little of which was

11、 ever repaid. He claimed to have found more than 500 uses for rubber and received patents in all countries except England, where Thomas Hancock had invented vulcanization in 1843. When Goodyear died in 1860, he left his wife and six children $200,000 in debt.,3. 单质硫的物理性质,弹性硫的形成实验,硫的相对粘度与温度的关系,当温度升高时

12、，S8环断裂形成链状分子，粘度增大，颜色变深。,温度约473K时粘度最大，再升高，则长链断裂为小分子粘度变小，颜色变浅。,4. 硫的化学性质,硫在空气中燃烧,2018/10/7,刘晓瑭,16,9.3 硫和硫化物,9.3.1 单质硫9.3.2硫化氢和氢硫酸9.3.3硫化物,3. 硫化氢的性质,其还原性体现在：,2018/10/7,刘晓瑭,21,9.3 硫和硫化物,9.3.1 单质硫9.3.2硫化氢和氢硫酸9.3.3硫化物, 硫化物的难溶性 许多金属离子在溶液中与硫化氢或硫离子作用，生成溶解度很小的硫化物。,2. 重金属硫化物, 硫化物的颜色 大多数为黑色，如FeS、CoS、NiS、Ag2S、Cu

13、S、HgS(也有红色的HgS)、PbS等。 少数为其它颜色，如 ZnS白色，MnS浅粉色，CdS、SnS2黄色，Sb2S3、Sb2S5橙色，SnS褐色。,Image of fluorescence in various sized Cadmium Selenide Quantum Dots.,Photoluminescence of Quantum Dots,2018/10/7,刘晓瑭,34,2018/10/7,刘晓瑭,35,目 录,9.1氧族元素的通性9.2 氧9.3 硫和硫化物9.4硫的含氧化合物9.5硒和碲,2018/10/7,刘晓瑭,36,9.4硫的含氧化合物,9.4.1 硫（）的含氧

14、化合物9.4.2 硫（）的含氧化合物9.4.3 硫的其他氧化态的含氧化合物,(1) SO2的结构 S：sp2杂化，OSO119.5，SO键长143.2 pm SO2是极性分子,1. SO2,2018/10/7,刘晓瑭,43,9.4硫的含氧化合物,9.4.1 硫（）的含氧化合物9.4.2 硫（）的含氧化合物9.4.3 硫的其他氧化态的含氧化合物,型晶体：石棉链状结构 (SO3)n 分子，是由SO4四面体连成一个无限长链分子。,2. 硫酸,(2) 浓H2SO4的性质,(3) 硫酸盐(正盐和酸式盐), 硫酸盐的性质, 易形成复盐 复盐是由两种或两种以上的简单盐类所组成的结晶化合物，常见的组成有两类：

15、 M2SO4MSO46 H2O： M：NH4, Na, K, Rb, Cs； M：Fe2, Co2, Ni2, Zn2, Cu2, Hg2； 如摩尔盐 (NH4)2SO4FeSO46 H2O 镁钾矾 K2SO4MgSO46 H2O。, MSO4 M2(SO4)324 H2O： M：V3, Cr3, Fe3, Co3, Al3, Ga3 等， 如明矾 K2SO4A12(SO4)324 H2O、 铬矾 K2SO4Cr2(SO4)324 H2O。,硫酸盐分解与温度的关系为： 同族，等价金属硫酸盐的热分解温度从上到下升高: MgSO4 (895 )CaSO4 (1 149 )SrSO4 (1 374

16、) 若同种元素能形成几种硫酸盐，则高氧化态硫酸盐 的分解温度低: Mn2(SO4)3 (300 )MnSO4 (755 ) 若金属阳离子的电荷相同、半径相近，则 8e 构型比18e 构型的阳离子硫酸盐的分解温度要高： CdSO4 (816 ) CaSO4 (1 149 ),2018/10/7,刘晓瑭,58,9.4硫的含氧化合物,9.4.1 硫（）的含氧化合物9.4.2 硫（）的含氧化合物9.4.3 硫的其他氧化态的含氧化合物9.4.4 硫的含氧酸的衍生物,3. 连二亚硫酸及其盐,（1）结构,Na2S2O4 . 2 H2O是染料工业上常用的还原剂，称为保险粉。,（2）制备和性质,小 结,2018

17、/10/7,刘晓瑭,71,9.4硫的含氧化合物,9.4.1 硫（）的含氧化合物9.4.2 硫（）的含氧化合物9.4.3 硫的其他氧化态的含氧化合物9.4.4 硫的含氧酸的衍生物,1. 酰卤,2. 卤磺酸,附录： 硫的卤化物,硫的氮化物（sulfur-nitrogen compounds）,2018/10/7,刘晓瑭,80,目 录,9.1氧族元素的通性9.2 氧9.3 硫和硫化物9.4硫的含氧化合物9.5硒和碲,2018/10/7,刘晓瑭,81,9.5 硒和碲,9.5.1 单质9.5.2 硒和碲的氢化物9.5.3 硒和碲的含氧化合物,2018/10/7,刘晓瑭,83,9.5 硒和碲,9.5.1

18、单质9.5.2 硒和碲的氢化物9.5.3 硒和碲的含氧化合物,H2Se、H2Te的水溶液是氢硒酸和氢碲酸。25，1105 Pa下饱和溶液中，H2Se的浓度为 0.084 molL3，H2Te为 0.09 molL3 (H2S为 0.1 molL3)，其酸性均比H2S强。其次序为： H2Se Ka11.29104 Ka2 1.01011 H2Te Ka12.3103 Ka21.61011 比较： H2S Ka11.07107 Ka21.261013,2018/10/7,刘晓瑭,86,9.5 硒和碲,9.5.1 单质9.5.2 硒和碲的氢化物9.5.3 硒和碲的含氧化合物,H2SeO4、HSeO4、SeO42、SeO3都不如相应的硫化合物稳定。,2018/10/7,刘晓瑭,93,