由下表提供数据及相关物质结构知识,反应1:SiCl
4(g)+2H
2(g)=Si(g)+4HCl(g),反应2:Si(g)+O
2(g)=SiO
2(g),则反应1和反应2的反应热为

硅的晶体结构

化学键
| Si-Cl
| H-H
| Si-Si
| H-Cl
| O=O
| Si-O
|
键能kJ/mol)
| 360
| 436
| 176
| 431
| 498
| 460
|
A.+236kJ/mol,-990kJ/mol | B.-116kJ/mol,-990kJ/mol |
C.-116kJ/mol,-70kJ/mol | D.+236kJ/mol,-70kJ/mol |