Ga. Ayoko et J. Arabel, ELECTRON-TRANSFER AT TETRAHEDRAL COBALT(II) .5. KINETICS OF PERMANGANATE ION REDUCTION, Transition metal chemistry, 19(2), 1994, pp. 212-214
The kinetics and mechanism of the reduction of MnO4-by CoW12O4O6- in a
queous HClO4 were studied. The reaction follows the rate law: -d[MnO4-
]/dt = 5 K(a)k[H+][MnO4-][CoW12O4O6-] with K(a) = 2.99 x 10(-3) mol-1
dm3 and k = 2.00 +/- 0.02 x 10(3) dm6 mol-2 s-1 at 25-degrees-C. Close
agreement between k(obs) and k(calc) on the basis of Marcus theory su
ggest an outersphere mechanism operates. Alkali metal ions catalyse th
e reaction in the order K+ > Na+ > Li+ and this result has been ration
alized.