已知:(1)Fe2O3(s) + 3CO(g) ="=" 2Fe(s) + 3CO2(g) △H1= -26.7 kJ/mol
(2)3Fe2O3(s) + CO(g) ="=" 2Fe3O4(s) + CO2(g) △H2= -50.75 kJ/mol
(3) Fe3O4(s) + CO(g) ="=" 3FeO(s) + CO2(g) △H3= -36.5 kJ/mol
计算反应:2FeO(s) + 2CO(g) ="=" 2Fe(s) + 2CO2(g)的△H(要有计算过程)。