FUW TRENDS IN SCIENCE & TECHNOLOGY JOURNAL
(A Peer Review Journal)
e–ISSN: 2408–5162; p–ISSN: 2048–5170
keywords: Kinetics, mechanism, neutral red, bromate ion
The kinetics and mechanism of redox reaction of neutral red, NR+, and bromate ion, BrO , was studied in aqueous hydrochloric acid medium under pseudo-first order conditions at 25 ± 1°C, [H+] = 2.0 × 10-2 mol dm-3, I = 0.5 mol dm-3 (NaCl) and λmax = 525 nm. The reaction was first order with respect to both [NR+] and [BrO ], and second order with respect to [H+]. The rate of the reaction displayed a positive Bronsted-Debye salt effect. There was no evidence of the formation of an intermediate complex of significant stability and free radicals were probably not present in the reaction. The observations above, coupled with the result of Michaelis-Menten plot suggests an outer sphere mechanism for the reaction. The reaction obeys the rate equation: . A plausible mechanism has been proposed for the reaction.
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