A Note on the Nature of Ionic Hydrations and Hydrophobic Interactions in Aqueous Solutions

A theoretical consideration on the nature of solute-water and solute-solute interactions in aqueous solutions has been performed. Thermodynamic functions for the creation of cavities accommodating solute molecules were calculated by the use of the scaled particle theory, and the “negative hydration” effect of univalent ions such as Rb+, Cs+, Cl−, I− etc., which was proposed first by Samoilov, Krestov and others, was interpreted and discussed. The nature of solute-water and solute-solute interactions in aqueous solutions of inert gases and hydrocarbons was elucidated in comparison with the interactions in nonaqueous solutions of those solutes.