Sound thermodynamic foundation based on the truncated Pitzer expansion Utilization of 309 experimental data points pertaining to 20 ILs of different classes Accurate prediction of the molar enthalpy of vaporization of 62 ILs based on the Clausius-Clapeyron equation Thorough comparison with two predictive models developed based on the zero-pressure liquid fugacity approach AARDs of 6.97% and 5.89% in the prediction of the vapor pressure and enthalpy of vaporization of ILs