Redox kinetics of the reaction of hydroxylamine hydrochloride (H2NOH.HCl) and BrO3 – was carried out in aqueous acidic medium, at temperature of 29.5 ± 0.5ºC; ionic strength μ = 1.0 mol dm–3 (NaCl), [H+] = 1.0 x 10–2 mol dm–3 (HCl). The reaction showed a stoichiometry of 1:1.3, first order kinetics in both [NH3OH+] and [BrO3 –], dependence on acid concentrations, positive salt effect, catalysis due to anions and absence of evidence of intermediate complex formation. Rate equation for the reaction has been proposed as: –d[NH3OH+]/ dt =(a[H+])[ NH3OH+][ BrO3 –]. The second order rate constant for the NH3OH+– BrO3 – reaction was found to be 0.233 dm3 mol–1 s–1. Based on the results obtained experimentally, the outer – sphere mechanism is suggested for the reaction.
