Stripping polarography and the reduction of copper(II) in sea water at the hanging mercury drop electrode

Abstract

An approximate but general theoretical treatment for reversible and irreversible stripping polarographic systems is presented. The treatment is based on the development of an average current (i), which at plating times exceeding 15 s. is analogous to the instantaneous current in d.c. polarography. Plots of i vs. (E – E°) are generated for reversible and irreversible waves and are discussed for the reduction of copper(II) in sea water as an example. From stripping polarography and anodic stripping voltammetry, this work indicates that the overall reduction of copper(II) at the natural pH is kinetically hindered and thus is “irreversible”. The reversibility and the determination of copper in sea water by a.s.v. can be improved by acidification and/or by the addition of ethylenediamine.