On the elucidation of mechanisms of electrode reactions by combination of a.c.-and faradaic rectification polarography. Application to the Zn2+/Zn(Hg) and Cd2+/Cd(Hg) reduction

Abstract

The theory of faradaic rectification polarography is extended to systems of higher order stoichiometry. The couples Zn2+/Zn(Hg) in 0.5 M MgSO4 and Cd2+/Cd(Hg) in 1 M KCl are studied with the aid of this technique in a wide potential range. The Zn2+/Zn reaction is interpreted as a multistep mechanism. The Cd2+/Cd reaction did not appear to be a simple linear reaction. Some higher order mechanisms are tested using the measurements