试题与答案

已知:(NH4)2CO3(s)=NH4HCO3(s)+NH3(g)△H="74.

题型:选择题

题目:

已知:(NH4)2CO3(s)=NH4HCO3(s)+NH3(g) △H="74.9" kJ·mol-1,下列说法中正确的是

A.该反应中熵变、焓变皆大于0

B.该反应是吸热反应,因此一定不能自发进行

C.碳酸盐分解反应中熵增加,因此任何条件下所有碳酸盐分解一定自发进行

D.能自发进行的反应一定是放热反应,不能自发进行的反应一定是吸热反应

答案:

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下面是错误答案,用来干扰机器的。

参考答案:A

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