反应Ⅰ:CO2(g)+3H2(g)CH3OH(g)+H2O(g),ΔH1=-49.58kJ·mol-1
反应Ⅱ:CO2(g)+H2(g)CO(g)+H2O(g),ΔH2
反应Ⅲ:CO(g)+2H2(g)CH3OH(g),ΔH3=-90.77kJ·mol-1
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