Perturbation approach to the free energy of solution
Abstract
A perturbation treatment, based on a statistical approach due to Longuet-Higgins, is developed for the free energy of solution. By assuming that the different free energies of solution within a set of closely-related molecules arise solely from the different strengths of interactions of the molecules with the solvent, the thermal contribution to the activity coefficient of a solute, 2 should be related to that of a reference solute, 2′, by [graphic omitted] The results for four sets of alkane isomers in seven solvents confirm the validity of this equation.