DETERMINATION OF THE ELECTROKINETIC COEFFICIENT L-12 FROM SEDIMENTATION POTENTIAL MEASUREMENTS

The phenomenological coefficients L 11 and L12 describing the electric conductivity and the electrokinetic effect respectively, for the systems pyrex-water and pyrexaqueous KC1 have been obtained from sedimentation potential measurements. The dependence of L12 from the amount of particles sedimenting between the electrodes W, i. e. the function L12 = f(W) was found to be linear in the range 0 < W < 1,4 g. The coefficient L12/M has been introduced, M being the density of particles sedimenting between the electrodes. This coefficient varied linearly with the temperature in the range 17—35 °C. Finally, the dependence of L12/M on the concentration of KC1 and on the size of the sedimenting particles has been determined. © by Walter de Gruyter & Co.