北京化工大学：《无机化学》课程电子教案（课件讲稿，2015）Chapter 15 The elements of nitrogen family

15 The elements of nitrogen family 15.1 Outline on nitrogen family 15.2 The elemental substances of nitrogen family 15.3 The compounds of nitrogen 15.4 The compounds of phosphorus -15.5 The compounds ofAs,Sb and Bi

15.5 The compounds of As, Sb and Bi 15.4 The compounds of phosphorus 15.3 The compounds of nitrogen 15.2 The elemental substances of nitrogen family 15.1 Outline on nitrogen family §15 The elements of nitrogen family

15.1 Outline on nitrogen family The elements of nitrogen family(VA):N,P,As,Sb,Bi Valence electron configuration:ns2np3 N P As Sb Bi 氧化值 +5 +5 +5 +5 (+5) +3 +3 +3 +3 -3 -3 -3 (-3) 最大配 4 位数 6 6 6 6 M203 酸性 酸性 两性 两性碱性 MH; NH3 PH3 AsH3 SbHa BiH; 碱性减弱，稳定性下降

15.1 Outline on nitrogen family The elements of nitrogen family(VA)：N, P, As, Sb, Bi Valence electron configuration：ns 2np 3 N P As Sb Bi +5 +5 +5 (+5) +3 +3 +3 +3 氧化值 +5 | -3 -3 -3 (-3) 最大配 位数 4 6 6 6 6 M2O3 酸性 酸性 两性 两性 碱性 氨 膦 胂 SbH3 BiH3 MH3 碱性减弱，稳定性下降 NH3 PH3 AsH3 SbH3 BiH3

15.2 The elemental substances of nitrogen family N2 is colorless and odorless gas.N2 is chemically inert.It will react directly with many metals (such as Li,Ca,Mg)when heated to give ionic nitrides.Nitrogen is also easily converted to a liquid(b.p,-195.8 C)and can dissolve in water slightly

N2 is colorless and odorless gas. N2 is chemically inert. It will react directly with many metals (such as Li, Ca, Mg) when heated to give ionic nitrides. Nitrogen is also easily converted to a liquid (b.p, -195.8°C) and can dissolve in water slightly. 15.2 The elemental substances of nitrogen family

The allotropes of phosphorus 黑磷←高温高压 一白磷 隔绝空气400C红磷 net framework, P:chemically relatively stable, conductive, active,autoignite in combust at insoluble in org. air,soluble in T>400°C,insoluble solvent. nonplolar solvent. in org.solvent. Self-ignite in air白 combustion of P 白磷红磷 磷空气中自燃 磷的燃烧

白磷 红磷 The allotropes of phosphorus 黑磷高温高压  白磷隔绝空气 400 C 红磷 P4 : chemically active, autoignite in air, soluble in nonplolar solvent. relatively stable, combust at T>400C, insoluble in org. solvent. combustion of P 磷的燃烧 Self-ignite in air白 磷空气中自燃 net framework， conductive, insoluble in org. solvent

白磷的结构 红磷的结构 两 Bi 黑磷的结构 N2,P:metalloid, As,Sb:quasi-metal, Bi:metal D

As Sb Bi N2 , P: metalloid， As, Sb: quasi-metal， Bi: metal 白 磷 的 结 构 红 磷 的 结 构 黑磷的结构

15.3 The compounds of nitrogen 1.Hydride of nitrogen ◆ ammonia(NH3) molecular N:sp3 hybridization,triangular structure: pyramid molecular structure N 100.8pm 107.3 …H H H

15.3 The compounds of nitrogen molecular structure： N：sp3 hybridization, triangular pyramid molecular structure 1. Hydride of nitrogen N H 107.3o .. H H  ammonia (NH3 )

Preparation: In laboratory: 2NH CI+Ca(OH)2>CaCl2 +2H2O+2NH3 (g) In industry process: N+3H2 450-500C 30MPa Fe >2NH Chemical properties: 1 Soluble in water forming monoprotic weak base NH,+H,O-NH,H,O-NH +OH 2Strong reducing ability 4NH3 +302(pure)->2N2 +6H2O 4NH,+50,(ar)o4N0+6H,0

In industry process: 2NH Cl Ca(OH) CaCl 2H O 2NH (g) 4  2  2  2  3 N2 3H2 2NH3  450 ~500  C 30MPa  Fe Preparation： In laboratory： Chemical properties： ① Soluble in water forming monoprotic weak base ② Strong reducing ability _ NH3 H2O NH3 H2O NH4 OH  4NH 5O (air) 4NO 6H O 4NH 3O (pure) 2N 6H O 2 P t 3 2 3 2 2 2       800oc

3 coordination reaction H+NH3→NH, Ag+2NH3-→[AgNH3)2] 4Substitution reaction 2NH,+2Na- E→2 NaNH,+, Na loses e,H+get e ◆NH2-NH,联氨（肼），NH氏亚氨基，N<氮化物 hydrazine ◆NH2OH羟氨，Ammonium hydroxide

④ Substitution reaction         Ag 2N H [Ag(NH ) ] H N H N H 3 3 2 3 4 2 2 570 C 2NH3  2Na 2NaNH  H  催化 ③ coordination reaction NH2 -NH2联氨(肼)，NH 亚氨基，N 氮化物 hydrazine NH2OH 羟氨, Ammonium hydroxide Na loses e, H+ get e

◆Ammonium salts 1 Most ammonium salts are colorless crystals and soluble in water hydrolysis:NH +H2O=HO+NH3 The structure of NH: N:sp3 hybridization,tetrahedron Identification of NH: Litmus paper method(石蕊试纸法)：pH range::5-8遇酸变红 遇碱变蓝 Nessler reagent(K2HgI4:phenomena is红棕到深褐 N:2I0NH)73

① Most ammonium salts are colorless crystals and soluble in water H N H H H   Ammonium salts Litmus paper method(石蕊试纸法)：pH range: 5 -8 遇酸变红， 遇碱变蓝  NH4 The structure of ： Nessler reagent (K2HgI4 ): phenomena is 红棕到深褐 N：sp3 hybridization, tetrahedron Identification of NH4 +： NH ]I(s) 7I 3H O Hg Hg NH 2[HgI ] 4OH [O 2 2 2 4  4     - - - hydrolysis： + H2O H3O+ + NH3  NH4

2 Poor thermal stability ammonium salts of non-oxidizing volatile acids NH,CIa→NH(g)+HC(g (NH)2 CO3-A >2NH3 (g)+CO2(g)+H2O(g) NH,HCO3-A >NH;(g)+CO2 (g)+H2O(g) ammonium salts of non-oxidizing and non- volatile acids NH4)3PO4△→3NH3(g)+H3PO4 (NH)2SO->NH (g)+NH,HSO

ammonium salts of non-oxidizing volatile acids N H HCO N H (g) C O (g) H O(g) (NH ) C O 2N H (g) C O (g) H O(g) N H C l N H (g) HCl(g) 4 3 3 2 2 4 2 3 3 2 2 4 3            ammonium salts of non-oxidizing and non￾volatile acids 4 2 4 3 4 4 4 3 4 3 3 4 (NH ) SO NH (g) NH HSO (NH ) PO 3NH (g) H PO       ② Poor thermal stability