Transfer free energies for some univalent chlorides from H₂O to D₂O from measurements of ion exchange membrane potentials

The cells (Chemical Equation Presented) with representing a cation exchange membrane and M representing the ions Li+, Na+, K+, Cs+, NH4+, and (CH3)4N+ have been investigated. The e.m.f. values show a spontaneous transfer of salt from D2O to H2O. The measurements, combined with published enthalpy data and with additional measurements of systems of H2O-D2O mixtures, yield entropy values which are interpreted according to Frank's "iceberg" theory.