Electrical Conductivity of Mixed Electrolytes: Modeling within the Mean Spherical Approximation

The purpose of this study is to predict the electrical conductivity of an electrolyte solution containing several simple ionic species. Explicit equations of the MSA-transport theory for the electrical conductivity in this complex solution are given. The theoretical conductivity of simple salts is first compared to experimental results of the literature to deduce the sizes of the ions. These sizes allow us to calculate the conductivity for a mixture of several ionic species without any additional parameter. We have also measured the electrical conductivity of solutions of LiCl, NaCl, and KCl and of KBr and MgCl(2) at 25 degrees C. A very good agreement between theoretical calculations and experimental values is obtained for each studied system.