Preferential solvation. Part 3.—Binary solvent mixtures

Abstract

The quasi-lattice–quasi-chemical theory of preferential solvation that has been applied previously to the solvation of ions in mixed solvents has been applied to the binary solvent mixtures themselves. The preferential solvation δx₂₍₁₎, i.e. the fraction of molecules of component 2 around molecules of component 1 relative to the mean mole fraction of the bulk of the mixture, has been derived for 23 mixtures of polar solvents. This is based on a single fitting parameter (the ratio of the lattice parameters of the components) applied to the excess Gibbs free energy of each mixture.