Partial Molar Volumes of Butyltriethylammonium Iodide in Single Nonaqueous Solvents at 298.15 K

Abstract

Densities of butyltriethylammonium iodide solutions in methanol, 2-propanone, acetonitrile, and nitrobenzene were measured at 298.15 K. Using published values for the Debye-Hu ¨ckel limiting slopes A V , apparent molar volume data were fitted to the Redlich-Rosenfeld-Meyer and the Pitzer equations, allowing the evaluation of partial molar volumes at infinite dilution V j 0 and deviation parameters B V . The results show a similarity between the V j 0 values for the "asymmetrical" quaternary ammonium salt (where the cation has a slightly extended alkyl group) and those for the corresponding "symmetrical" salt (presenting the four alkyl groups identical to the longest of them). Parameter B V is shown to be solvent dependent.