The Treatment of Ionic Solutions over the Entire Miscibility Range

Conductance and thermodynamic properties are considered for several ionic systems continuously miscible from the fused salt to dilute solution in water or another polar solvent. Over most of the composition range, the activities of the respective components of the ionic systems show the same patterns of behavior and can be represented by the same equations that were developed for nonelectrolytes. Consideration is also given to ionic systems of large but finite solubility, including mixed electrolytes. The dominant factor in the behavior of these systems is the strength of ion solvation in competition with intermolecular forces in the solvent and direct interionic forces. Strong ion solvation yields negative deviations from ideal solution behavior and vice versa.