Electrode processes of nickel(II) at mercury electrodes in aqueous solutions of iodides

Abstract

Summary The electrode behaviour of nickel(II) in aqueous solutions of iodides at mercury electrodes has been investigated using polarographic and voltammetric methods. It was found that at 25°C in moderately concentrated iodides NiI + is formed which is reduced with the standard rate constant of the order 10 −5 cm s −1 , at 50°C. At higher temperatures, 50–85°C, and very high ionic strength the formation of NiI 2 was found which is reduced under such conditions with the standard rate constant of the order 10 −3 cm s −1 . The detailed mechanism of both processes is discussed.