Solvation of cobalt(II) and perchlorate ions in binary mixtures of donor solvents

Abstract

The enthalpies of solution, (Δ_sH°) of sodium perchlorate have been measured in binary mixtures of water with methanol (MeOH), N,N-dimethylformamide (DMF) and dimethyl sulfoxide (DMSO) over the whole range of solvent composition. The data and the literature enthalpies of transfer, (Δ_tH°), for sodium ion in these mixtures and for perchlorate ion in water–N,N-dimethylacetamide (DMA) mixtures have been used to determine the ionic contributions to the previously reported enthalpies of transfer for cobalt(II) perchlorate from water to the binary mixtures. The results have been compared with the enthalpies of transfer of cobalt(II) and perchlorate ions from water to AN–H₂O mixtures and from DMSO to AN–DMSO mixtures, presented earlier (AN, acetonitrile). The ionic transfer data have been discussed in terms of the donor properties and the bulk structure of the binary mixtures investigated.