USING ION-SELECTIVE ELECTRODES TO STUDY T HE THERMODYNAMICS OF SOLUTION .5. THE STANDARD GIBBS FREE-ENERGIES AND ENTROPIES OF TRANSFER OF KCL FROM H2O TO DMF-H2O MIXTURE AT 7 TEMPERATURES FROM 283.15K TO 318.15K

The standard electromotive forces of the reversible cells without liqu id junction consists of the Corning Monovalent cation Electrode and ch loride selective electrode, namely, Cl- selective electrode \ KCl(m), w or \ M+ glass-electrode have been measured, and the standard Gibbs f ree energies of transfer of KCl from water to N, N-dimethylformamidewa ter mixtures have been calculated. The standard transfer entropies hav e been also calculated from temperatures coefficient of DELTAG(t)degre es at seven temperatures from 283.15 K to 318.15 K. The behaviour of t he change of DELTAG(t)degrees and DELTAS(t)degrees; with organic compo sition and temperature have been given, It is found that the changing tendency of DELTAS(t)degrees(KCl) and DELTAS(t)degrees (NaCl) from H2O to H2O-DMF mixture are different. The corresponding change of solvati on of KCl from the pure water to mixed solvents and its influence on t he structure of the liquid studied were discussed.