The standard electromotive forces of the reversible cells consisted of the Corning monovalent general cation selective electrode (M + ISE) and chloride selective electrode (Cl ISE), namely Cl --ISE｜RbCl( m ),H 2O(1- x ),DMF( x )｜M +-ISE have been measured, and the standard free energies of transfer(Δ S t ) of RbCl from H 2O to mixtures of H 2O DMF have been calculated, the standard transfer entropies(Δ S t ) have been also calculated from temperature coefficients of Δ G t of RbCl at seven temperatures from 283.15 K to 318.15 K. The behavior of change of Δ S t of RbCl with experimental temperature and mole fraction ( x ) of DMF in the mixed solvents and its influence on the structure of the mixed solvents were discussed on the basis of solvation theory ofelectrolyte solution.
