Viscosity measurements of some 1:1 electrolytes in acetic acid+ water mixtures at 25°C

Abstract

The relative viscosities of solutions of some alkali metal acetates and tetraalkyl ammonium salts have been measured in the concentration range 5 -700 × 10^-4 mol dm^-3 in acetic acid + water mixtures containing 20, 40, 60, 80, 90, 95 and 100 wt % acetic acid at 25°C. The viscosity data have been analyzed using Jones Dole equation. The viscosity <i>B</i>-coefFicient, an ion-solvent interaction parameter, has been found to be positive for all the electrolytes in all the systems. The ionic viscosity <i>B_± </i>coefficients have been calculated by taking Bu₄NBPh₄ as reference electrolyte. The viscosity <i>B-</i>coefficient for all the alkali metal ions and tetraalkyl ammonium ions are found to increase upto 90 wt % acetic acid and 80 wt % acetic acid respectively indicating increase in extent of solvation and enhancement in structure. Li⁺

ion shows anomalous behavior while Br^- ion shows structure breaking effect in the water rich region of the solvent mixture.