(1)式:CH3CH2OH(l)+3O2(g)=2CO2(g)+3H2O(l) △H1 =1366.8kj/mol
(2)式:2H2(g)+O2(g)=2H2O(l) △H2 = -571.6kj/mol
所求反应(3)式=(2)式-(1)式:
2CO2(g)+ 2H2(g)+H2O(l) =CH3CH2OH(l)+ 2O2(g)
△H3= △H2 - △H1= -571.6 -(1366.8)= -1938.4 (kJ/mol)
(1)式:CH3CH2OH(l)+3O2(g)=2CO2(g)+3H2O(l) △H1 =1366.8kj/mol
(2)式:2H2(g)+O2(g)=2H2O(l) △H2 = -571.6kj/mol
所求反应(3)式=(2)式-(1)式:
2CO2(g)+ 2H2(g)+H2O(l) =CH3CH2OH(l)+ 2O2(g)
△H3= △H2 - △H1= -571.6 -(1366.8)= -1938.4 (kJ/mol)