①CO(g)+2H2(g)CH3OH(g) △H1=-90.7kJ•mol-1 K1
②2CH3OH(g)CH3OCH3(g)+H2O(g) △H2=-23.5kJ•mol-1 K2
③CO(g)+H2O(g)CO2(g)+H2(g) △H3=-41.2kJ•mol-1 K3
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