GIBBS TRANSFER ENERGIES AND SOLVENT TRANSPORT NUMBERS OF SOME COPPER(II) SALTS IN METHANOL-DIMETHYLFORMAMIDE MIXTURES

Standard Gibbs energies of transfer have been determined for copper(II ) iodate, benzoate and formate at 30 degrees C in methanol-dimethylfor mamide mixtures by solubility measurements. Single-ion transfer energi es were obtained by using the negligible liquid junction potential ass umption, along with relevant literature data, and are in excellent agr eement with values estimated from the reference electrolyte (tatb) ass umption. The results obtained indicate that all of these salts are het eroselectively solvated in these mixtures, with CU2+ being preferentia lly solvated by dmf and the anions by MeOH. This model is consistent w ith calculations based on the quasi-lattice quasi-chemical theory of M arcus and with solvent transport numbers obtained from e.m.f. measurem ents.