Ionic B coefficients of sodium and bromide ions in formamide + water mixtures

Abstract

The viscosities of sodium tetraphenylborate and tetraphenylphosphonium bromide in formamide + water mixtures have been measured at 30, 35 and 40 °C and the corresponding B coefficients of the Jones–Dole equation have been calculated. From these B values, the ionic B coefficients of sodium and bromide ions have been determined, assuming that the equality B_Ph4P⁺=B_Ph4B^– holds for the different solvent mixtures. The results are discussed in terms of solvent structural changes and preferential solvation.