Partial molar volumes and viscosities of some multicharged electrolytes in dimethyl sulphoxide-water mixtures

Abstract

Partial molar volumes and viscosities of ammonium aluminium sulphate and potassium aluminium sulphate have been determined in dimethyl sulphoxide (DMSO) + water (5, 10, 15 and 20 wt %) mixtures at different concentrations and temperatures. The density data have been analysed using Masson's equation. The limiting apparent molar volumes (ϕ<img src='http://www.niscair.res.in/jinfo/zerov.gif' border=0>) and the slopes (S<img src='http://www.niscair.res.in/jinfo/starv.gif' border=0>) have been interpreted in terms of solute-solvent and solute-solute interactions, respectively. The ϕ<img src='http://www.niscair.res.in/jinfo/zerov.gif' border=0> values vary with temperature as a power series of temperature. Structure making/breaking capacities of the multi-charged electrolytes have been inferred from the sign of (<em>∂</em>²ϕ<img src='http://www.niscair.res.in/jinfo/zerov.gif' border=0>/<em>∂</em> <em>T</em>²)<em>. </em>Both multi-charged electrolytes behave like the symmetrical tetraalkylammonium salts and act as structure makers/promotors. The experimental results of viscosity have been analysed using the Jones-Dole equation. The activation parameters of viscous flow have been obtained to throw light on the mechanism of viscous flow.