Question

【题目】已知H2(g)＋Cl2(g)="2HCl(g)" ΔH＝-184.6 kJ·mol-1，则反应HCl(g)=1/2H2(g)＋1/2Cl2(g)的ΔH为

A. ＋184.6 kJ·mol-1 B. -92.3 kJ·mol-1

C. ＋92.3 kJ D. ＋92.3 kJ·mol-1

Answer 1

【答案】D

【解析】试题分析：H2(g)+Cl2(g)=2HCl(g) △H= -184.6kJ·mol-1，则2HCl(g)= H2(g)+Cl2(g)，△H=184.6kJ·mol-1，所以HCl(g)＝1/2H2(g)+1/2Cl2(g)的△H=186.6/2=+92.3kJ·mol-1；所以答案为D。