Separation of viscosity B coefficients into ionic contributions. Part 2.—Tetrabutylammonium tetrabutylborate and tetraphenylphosphonium tetraphenylborate in hexamethylphosphoric triamide

Abstract

The relative viscosities and densities of solutions of tetrabutylammonium tetrabutylborate, tetrabutylammonium bromide, tetraphenylphosphonium tetraphenylborate and tetraphenyl-phosphonium bromide in hexamethylphosphoric triamide have been measured at 25 and 35 °C. Viscosity B coefficients and apparent molar volumes at infinite dilution have been determined for these salt systems. Two independent values of the viscosity B coefficient for the bromide ion have been obtained and a new set of ionic B coefficients for the alkali-metal halides in hexamethylphosphoric triamide have been calculated. The various contributory factors to the magnitude of the ionic B coefficients are discussed.