Find out which component is the limiting reagent and select that as base component. If none of the reagents are exhausted, I believe you can choose any reactant as base component. Only thing to note is that the enthalpy of reaction would be calculated according to that selected base component.
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How does one choose what should be the base component in an equilibrium reaction?
Find out which component is the limiting reagent and select that as base component. If none of the reagents are exhausted, I believe you can choose any reactant as base component. Only thing to note is that the enthalpy of reaction would be calculated according to that selected base component.