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