Original scientific paper

Electrokinetic Studies in Dispersed Systems. V. The Zeta Potential of Agl Precipitates in Mixed Solvents

V. Pravdić ; Institute »Ruder Boskovic« and Laboratory of Physical Chemistry, Faculty of Science,. University of Zagreb, Zagreb, Croatia, Yugoslavia
M. Mirnik ; Institute »Ruder Boskovic« and Laboratory of Physical Chemistry, Faculty of Science,. University of Zagreb, Zagreb, Croatia, Yugoslavia

Abstract

The influence of acetone-water, dioxane-water and methanolwater
solvent mixtures upon the electrokinetic potential of Ag!
precipitates has .been studied. The same dielectric constant of the
medium yields approximately the same zeta-potential only if the
activity of the reversible electrode potential determining ions
(constituent ions) is sufficiently large to determine a stable zetapotential in aqueous solution of the same composition. In the isoelectric region, in the case of the theoretically balanced positive
and negative potential determining ions adsorption, the influence
of solvent dipoles is predominant and specific, and the dielectric
constant is not a measure of the electrokinetic potential. The
mecha nism of the zeta-potential determining processes is manifold
and any extrapolation of a single parameter of the system is
insufficient to give answers of general importance.

Keywords

Hrčak ID:

208609

URI

https://hrcak.srce.hr/208609

Publication date:

15.10.1960.

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