ENERGIES OF HYDRATION OF CHARGED SPECIES

On the basis of experimental data for the Volta potentials of the mercury/solution interface and of the most reliable thermodynamic functions, the hydration energies of individual ions has been revised. Unfortunately an incorrect value for the standard potential of the cesium electrode was used in calculating the real energy of hydration of the Cs** plus ions. Using the correct value, of minus 2. 923 V one finds alpha **C//s** plus ///H//2//O equals minus 2. 87 eV ( minus 276. 81 kJ/mole). This in turns gives rise to a change in the real ( alpha **H** plus ///H//2//O) and chemical ( mu **H** plus ///H//2//O energy of hydration of the hydrogen ions which are obtained via data for the alkali-metal cations. The corrected values of alpha **H** plus ///H//2//O and mu **H** plus ///H//2//O are minus 1084. 0 and minus 1096. 6 kJ/mole ( minus 259. 1 and minus 262. 1 kcal/mole), respectively.