①CH4(g)+H2O(g)⇌CO(g)+3H2(g)△H1=206.1kJ•mol﹣1
②CH4(g)+CO2(g)⇌2CO(g)+2H2(g)△H2=247.3kJ•mol﹣1
③CO(g)+H2O(g)⇌CO2(g)+H2(g)△H3
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