Free energies, enthalpies and entropies of transfer of electrolytes from propylene carbonate to dimethylsulphoxide + propylene carbonate mixtures and from methanol to acetonitrile + methanol mixtures at 25 °C. Further development of solvation theory

Abstract

The thermodynamic parameters for transfer of several electrolytes from propylene carbonate to dimethylsulphoxide + propylene carbonate mixtures and from methanol to methanol + acetonitrile mixtures have been measured.

These data are considered in terms of recently developed solvation theory. It is found that in both systems the data can be accounted for satisfactorily in terms of a two-state model of the solvation process. In the dimethylsulphoxide + propylene carbonate system only the interactions of the solute with its coordination-shell solvent molecules need to be considered. The methanol + acetonitrile system is more complex, and the interactions of the coordination-shell solvent molecules with the rest of the solvent must also be taken into account.