题目

下列各组热化学方程式中，化学反应的△H前者大于后者的是 ①C(s)＋O2(g) = CO2(g)；△H1    C(s)＋O2(g) = CO(g)；△H2 ②S(s)＋O2(g) = SO2(g)；△H3    S(g)＋O2(g) = SO2(g)；△H4 ③H2(g)＋O2(g) = H2O(l)；△H5   2H2(g)＋O2(g) = 2H2O(l)；△H6 ④CaCO3(s) = CaO(s)＋CO2(g)；△H7   CaO(s)＋H2O(l) = Ca(OH)2(s)；△H8 A．①        B．④           C．②③④          D．①②③ 答案：C

查看本题答案和解析