5.
下面均是正丁烷与氧气反应的热化学方程式(25℃、101kPa):
①C
4H
10(g)+
O
2(g)═4CO
2(g)+5H
2O(l);△H=﹣2 878kJ•mol
﹣1②C
4H
10(g)+
O
2(g)═4CO
2(g)+5H
2O(g);△H=﹣2 658kJ•mol
﹣1③C
4H
10(g)+
O
2(g)═4CO(g)+5H
2O(l);△H=﹣1 746kJ•mol
﹣1④C
4H
10(g)+
O
2(g)═4CO(g)+5H
2O(g);△H=﹣1 526kJ•mol
﹣1由此判断,正丁烷的燃烧热为( )