
%0 Journal Article
%A Temple, RB 
%A Thickett, GW 
%T The decomposition of permanganate in molten alkali-metal nitrates
%J Australian Journal of Chemistry
%D 1974/05/01
%V 27
%N 5
%P 943-953
%K 
%R https://doi.org/10.1071/CH9740943
%U https://www.publish.csiro.au/paper/CH9740943 
%X The decomposition of MnO4- has been studied in molten (K/Li)NO3 eutectic at temperatures between 150º and 200ºC. The rate of decomposition in a Pyrex vessel increased in the presence of traces of NO2-, Br- and CN- and of the manganate(1V) precipitate produced in the decomposition. Various transition and heavy metal ions were also found to accelerate the decomposition of MnO4- : the rate law appears to be     -d[MnO4-]/dt = k[Mn+]2/n[MnO4-]  where n = oxidation state of metal ion M which was added to the melt solution of MnO4- (in the presence of a fixed weight of insoluble reaction product). Nickel and cobalt(11) ions are oxidized by MnO4- to insoluble nickel(111) and cobalt(111) manganates(1V). Whilst NO2- produced by the thermal decomposition of NO3- appears to be the active reductant in (K/Li)NO3 melts, the reaction is complicated by being partly heterogeneous. The method of preparation of the reaction product critically affects the rate constant k. 
