E-R-PH AND E-R-M(KOH) DIAGRAMS FOR NICKEL AT 25-DEGREES-C

Based on the conclusion that no Ni(III) oxo compounds can exist in oxi dized nickel oxide electrodes with the total oxidation number 2.0 < z( Ni) < approx. 3.6 and that non-ideal solid solutions with a formal com position (1 -X-2) Ni(OH)(2) . X-2 NiO2 . x H2O Me are involved, E-r-pH and E-r-m(KOH) diagrams at 25 degrees C were calculated and graphical ly represented using the thermodynamic standard data determined for hy pothetical NiO2 . x H2O. The calculations were performed assuming alph a H2O = 1 in the en tire pH range (E-r-pH diagram) and considering the true water activity in KOH sol;lions of various concentrations (E-r-m (KOH) diagram).