10. 已知断裂1 mol气态分子AB中共价键变成气态A和B原子所需要吸收的能量叫A—B键的键能。几种化学键的键能数据如下表所示:
化学键 | Br-Br | F-F | H-F | H -Br | C-C | C≡C | H-H |
键能/(kJ·mol-1) | 194 | 157 | 568 | 366 | 348 | 812 | 436 |
下列说法正确的是
A.H-F键的稳定性比H- Br键弱 |
B.2HBr(g)=H2(g) +Br2(1) ΔH = +102 kJ·mol-1 |
C.F2(g)=2F(g) ΔH = -157 kJ·mol-1 |
D.2HBr(g) +F2(g) =Br2(g) +2HF(g) ΔH = -441 kJ·mol-1 |