①CO(g)+2H2(g) CH3OH(g) ΔH1=-90.7kJ·mol-1K1
②2CH3OH(g) CH3OCH3(g)+H2O(g) ΔH2=-23.5kJ·mol-1K2
③CO(g)+H2O(g) CO2(g)+H2(g) ΔH3=-41.2kJ·mol-1K3
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