It was not until dark _____he found _____he thought was the correct way to solve the problem. A.that; what B.that ;that C.when; that D.when ;what 答案:A 解析: 第一空考查强调句式的that,第二空用what是宾语从句中的主语。
充分燃烧一定量的丁烷(C4H10)气体放热Q kJ,完全吸收它产生的CO2且生成正盐时,需5 mol·L-1的KOH溶液100 mL.则丁烷的燃烧热为
A.
16Q kJ·mol-1
B.
8Q kJ·mol-1
C.
4Q kJ·mol-1
D.
2Q kJ·mol-1