Does the common use of a particular basis of accounting lead to an overstatement of the solubilities of CO2 and other gases in ionic liquids (ILs)? Consequently, is further discussion needed in judging the positive or negative deviations from ideality for CO2-IL solutions? Here, an alternative framework for mole fraction accounting previously proposed is more thoroughly considered. The results suggest that ILs tend to exhibit positive deviations from Raoult's Law when the cation and anion are taken as distinct molecular entities. An analysis of the influence of the variables associated with calculating CO2 mole fractions in ILs is provided which illustrates the large effects of solvent molecular weight on the calculations leading to the judgment of deviation from Raoult's Law.