Free energies of transfer of 1 : 1 electrolytes from water to nitrobenzene. Partition of ions in the water + nitrobenzene system

Abstract

Free energies of solution of 1 : 1 electrolytes in nitrobenzen have been obtained from solubility measurements. Free energies of transfer for these electrolytes from water to nitrobenzene were obtained by combining their free energies of solution in the organic solvent and in water. By using the convention suggested by Parker, the single-ion free energies of transfer for 8 cations and 6 anions have been obtained. These are compared with single-ion free energies of transfer obtained by calculation and with single-ion free energies of partition previously reported. Close agreement is found between the observed single-ion free energies of transfer from water to nitrobenzene and the single-ion free energies of partition.

On the basis of the experimental evidence shown in this work, it seems that in the partition of 1 : 1 electrolytes from water to nitrobenzene most of the ions are unhydrated in nitrobenzene. The influence of the cation as well as the anion in the partition of 1:1 electrolytes from water to nitrobenzene is discussed.