KINETICS OF OXIDATION OF THALLIUM(I) BY PERMANGANATE IN AQUEOUS HYDROCHLORIC-ACID MEDIUM USING THE STOPPED-FLOW TECHNIQUE

The permanganate-Tl-1 reaction in aqueous HCl was studied using the st opped-how technique. The reaction rate increases as both [H+] and [Cl- ] increase. It exhibits second-order kinetics and the rate law is give n by Equation 1: (1) - d[MnO4-]/dt = kK(1)K(4)[Mn-VII](T)[Tl-1](T)[H+] [Cl-]/{1 + K-4[H+]}{1 + K-1[Cl-]} where k is the rate constant of the slow step, and K-1 and K-4 are the respective formation constants of t he active form of the reductant, TlCl, and the protonated species of t he oxidant, HMnO4. A composite mechanism and rate law are proposed.