An Isotopic Investigation of the Mechanism of Permanganate Decomposition in Alkaline Solution

Abstract

IT has previously been shown¹ that in the presence of barium producing insoluble barium manganate, the decomposition of permanganate is of the first order with respect to: (a) the permanganate and (b) the hydroxide ion concentration. In the absence of barium the initial rate of decomposition as determined by means of the rotating disk method was found to be proportional to (a) the permanganate concentration, (b) the square of the hydroxide concentration, and (c) the reciprocal of the manganate concentration. These findings are in agreement with an equilibrium and a subsequent rate determining reaction according to the following scheme¹, which has previously been proposed by Symons³ leading to the kinetic equation: a—initial concentration of MnO₄⁻, b—alkali concentration, x—concentration of MnO₄=.