Self-Diffusion of Sodium, Chloride and Iodide Ions in Acetonitrile-Water Mixtures

Abstract

The self-diffusion coefficient of sodium, chloride and iodide ions in acetonitrile-water mixtures at 25.0 ± 0.05 °C has been measured in dependence on the salt molarity in the range 1.0·10-4 1.0-10-2mol/dm3. The ionic self-diffusion coefficients in infinitely diluted solutions have been computed. The influence of the solvent composition on the solvation of the ions is discussed. Preferential solvation of the ions by acetonitrile above 15mol% of acetonitrile has been found. An effect of the sodium ions on the formation of acetonitrile globules is postulated. © 1987, Walter de Gruyter. All rights reserved.