The relative efficiencies of a number of nitrite traps at different acidities and bromide ion concentrations

Abstract

A previously developed kinetic method (based on the reversible denitrosation of nitrosamines) for establishing quantitatively the relative efficiencies of nitrite traps has been extended (a) to cover a range of acidities 0.95–3.94M-H₂SO₄ and (b) to include a range of bromide ion concentrations 0.1–0.4M. For many of the traps the reactivity rate constant ratios do depend upon [H⁺] and also [Br^–], and the results can be explained in terms of the protonation equilibria of the various traps and also in terms of the reversibility of the initial nitrosation step (at high [Br^–]) for some of the traps. These results go some way towards explaining why there is not always good agreement between the relative reactivities established by this indirect method and a few cases where the rate constants have been measured directly by special fast-reaction techniques.