Kinetics and mechanism of the oxidation of 1-phenylsemicarbazide by hexacyanoferrate [III] ion in aqueous acid solution

ABSTRACT

Kinetics of the oxidation of 1-phenylsemicarbazide by hexacyanoferrate [III] ions has been investigated by stopped-flow technique as a function of reactants concentrations, temperature, ionic strength and pH. The redox reaction is first order with respect to hexacyanoferrate [III]. The depence of K[obs] on phenylsemicarbazide concentration [C[PSC]] is given by K[obs]=Y+XC[PSC] where Y is constant and X depends on hydrogen ion concentration. A detailed mechanism was proposed to explain these results. It was concluded that Fe [CN] 3-/6 and HFe [CN] 2-/6 are the reactive oxidizing species