Study of the mechanism of the oscillating reaction between bromate and phenol
In the oscillating reaction of bromate with phenol in the medium of 0.4M-H2SO4, the length of the induction period is governed by a kinetic equation for a second-order reaction with a stoichiometry 1 : 1. The concentration of quinones in the reaction mixture increases also according to a kinetic equation for a second-order reaction. The influence of various compounds is discussed, whose additions shorten or prolong the induction period, bring about oscillations in a nonoscillating reaction mixture, or change the frequency of these oscillations. From the comparison of the time dependences of the potential of a platinum and an ion-selective electrodes and of the limiting current of the quinones, a reaction mechanism was proposed.