例如:求C(石墨)+1/202(g)→C0(g)的热 效应? 已知:C(石墨) 02(g)→C02(g) () CO(g) 1/202(g)→C02(g) (2) ArHm1=-393.5 kJ-mol-1 ArHn2= -283.0kJmo1 (1)-(2)得C(石墨)+1/202g)→C0g) (3) △rHm°3=Hm1 ArHm2 例如:求 C(石墨)+1/2 O2 (g) → CO(g)的热 效应? 已知:C(石墨) + O2 (g) → CO2 (g) (1) CO(g) + 1/2O2 (g) → CO2 (g) (2) rHm 1 = - 393.5 kJ·mol-1 rHm 2 = - 283.0 kJ·mol-1 (1) - (2)得 C(石墨) + 1/2 O2 (g) → CO(g) (3) rHm 3 = rHm 1 - rHm 2