Polarographic studies on some organic compounds of arsenic. Part I. Substituent effects and the arsonic acids

Abstract

A study has been made of the polarographic behaviour of 12 arsonic acids. They give rise to a single well defined cathodic wave in acidic solutions below pH 3. The wave height is diffusion controlled and proportional to the concentration in the range 10^–5 to 10^–3M. The arsonic acids are reduced irreversibly to arsenobenzenes. The current-potential relationships have been examined and a linear relationship was found between the half-wave potential and the polar Hammett substituent constants. The use of polarography has been proposed for the quantitative functional analysis of the arsonic group, for the specific determination of nitrophenylarsonic acids and arsanilic acid in mutual mixtures, and for the specific determination of phenylarsonic acid and phenyl arsenoxide, also in mutual mixtures.