Selective Solvation of Silver(I) Acetate and Sulfate in Acetone-DMF Mixtures at 30 °C^*^*

The selective solvation of silver(I) sulfate and acetate has been investigated in the binary mixtures of N, N-dimethylformamide (DMF) and acetone at 30 °C by Gibbs energies of transfer and solvent transport number measurements.The Gibbs transfer energy of silver acetate from acetone to acetone + DMF mixtures increases upto xDMF=0.1 and thereafter decreases continuously upto pure DMF. The transfer energy of silver sulfate under the same conditions is negative and continuously decreases with the addition of DMF. While the Gibbs energy of transfer of silver(I) ion is negative and decreases continuously with the addition of DMF (on the basis of negligible liquidjunction potential method) the transfer energies of both the anions are positive and continuously increase upto xDMF=0.5. At xDMF0.6, however, the transfer energy of the sulfate ion is nearly constant till xDMF=0.8 and then decreases somewhat whereas that of the acetate ion is almost constant.The solvent transport number Δ of DMF for both the salts passes through a maximum at xDMF=0.35 with Δmax=7.2 for silver acetate and Δmax=11.5 for silver sulfate. These results suggest that both the salts are heteroselectively solvated in these mixtures with the silver ion being preferentially solvated by DMF and the anions by acetone. © by R. Oldenbourg Verlag, München 1984