题干
已知2mol H2 燃烧生成水蒸气放出484kJ热量，下列热化学方程式正确的是( )
A：H2O(l) ==H2(g)+ 1/2 O2(g)；△H =' +242' kJ·mol-1
B：2H2(g)+O2(g)==2H2O(l)；△H =' -' 484 kJ·mol-1
C：H2(g)+ 1/2 O2(g) ==H2O(g)；△H =' +242' kJ·mol-1
D：2H2(g)+O2(g)==2H2O(g)；△H ='-' - 484 kJ·mol-1
答案(点此获取答案解析）
D
