ON THE ADSORPTION VOLTAMMETRY OF THE BORON-BERYLLON-III-ASTERISK SYSTEM .2. MECHANISM OF THE ELECTROCHEMICAL REDUCTION OF BERYLLON-III AND ITS COMPLEX WITH B(III) IN ACETATE BUFFER

The adsorptive and voltammetric characteristics of Beryllon III and it s complex with B(III) at a mercury electrode have been investigated in acetate buffer. The adsorption phenomena were observed by sampled dc polarography normal pulse polarography, linear sweep voltammetry, and drop time curve measurement. It was found that (1) the reactant was an azo-group in Beryllon III or its complex with B(III) adsorbed on the surface of the mercury electrode; (2) for reduction of Beryllon III, t he product was a hydrazo compound and it was also adsorbed on the surf ace of the electrode; two electrons and two protons were irreversibly transferred in the overall reaction and the apparent transfer coeffici ent alphan (= 1.8) was measured experimentally; the irreversible elect ron transfer was followed by a chemical reaction; (3) for reduction of Beryllon III complex with B(III), the product was a hydrazo compound; two electrons and two protons were transferred reversibly in the reac tion; the hydrazo compound was desorbed from the surface of the electr ode, and the reversible electron transfer was followed by a chemical r eaction.