Determination of N-halogeno derivatives with ion-selective electrodes

Abstract

A method for analysing solutions of N-iodo derivatives (1 × 10^–2–1 × 10^–7 mol dm^–3) and N-bromo derivatives (1 × 10^–2–1 × 10^–6 mol dm^–3) has been developed. The N-halogeno derivative is reduced with sulphite ion and the halide concentration determined with an ion-selective electrode. N-Chloro derivatives undergo halogen exchange with bromide or iodide ion. The change in bromide or iodide concentration is determined with an ion-selective electrode and is equal to the concentration of the N-chloro derivative. Solutions 1 × 10^–6–1 × 10^–7 mol dm^–3 in N-chloro derivative can be analysed by this method.