A study of ion-solvent interactions of some tetraalkyl and multivalent electrolytes in propylene glycol-water mixtures

434-439The partial molar volumes and viscosities of some common tetraalkyl and multivalent electrolytes viz., ammonium sulphate, tetrabutylammonium bromide, aluminium ammonium sulphate and aluminium potassium sulphate have been determined in propylene glycol (PG) + water (4, 8, 12 and 16 wt%) mixtures. The density data have been analysed by means of Masson's equation. The partial molar volumes (φ) and slopes (S) have been interpreted in terms of ion-solvent and ion-ion interactions, respectively. Structure making/breaking capacities of the various electrolytes have been inferred from the sign of (δ2φ/T2). Both the multivalent electrolytes behave like the symmetrical tetrabutylammonium salt but not like common electrolyte in PG + H2O mixtures. The multivalent electrolytes and tetraalkyl salt act as structure makers/promotorswhile the common electrolyte acts as structure breaker. The experimental results of viscosity have been analysed using the Jones-Dole equation. The activation parameters of viscous flow have also been obtained to throw light on the mechanism of viscous flow