Kinetics and Mechanism of the Chlorate–Bromide Reaction

The chlorate–bromide reaction, ClO3 – + 6Br– + 6H+ → 3Br2 + Cl– + 3H2O, was followed at the Br3 –/Br2 isosbestic point (446 nm). A fifth-order rate law was found: 1/3 d­[Br2]/dt = k[ClO3 –]­[Br–]­[H+]3 (k = 5.10 × 10–6 s–1 L4 mol–4) at 25 °C and I = 2.4 mol L–1. At high bromide concentrations, the b...

Full description

Saved in:
Bibliographic Details
Published inInorganic chemistry Vol. 54; no. 21; pp. 10415 - 10421
Main Authors Sant’Anna, Rafaela T. P, Faria, Roberto B
Format Journal Article
LanguageEnglish
Published United States American Chemical Society 02.11.2015
Online AccessGet full text

Cover

More Information
Summary:The chlorate–bromide reaction, ClO3 – + 6Br– + 6H+ → 3Br2 + Cl– + 3H2O, was followed at the Br3 –/Br2 isosbestic point (446 nm). A fifth-order rate law was found: 1/3 d­[Br2]/dt = k[ClO3 –]­[Br–]­[H+]3 (k = 5.10 × 10–6 s–1 L4 mol–4) at 25 °C and I = 2.4 mol L–1. At high bromide concentrations, the bromide order becomes close to zero, indicating a saturation profile on bromide concentration, similar to the chloride saturation profile observed in the chlorate–chloride reaction. A mechanism is proposed that considers the formation of the intermediate BrOClO2 2–, similar to the intermediate ClOClO2 2– proposed in the mechanism of the chlorate–chloride reaction.
Bibliography:ObjectType-Article-1
SourceType-Scholarly Journals-1
ObjectType-Feature-2
content type line 23
ISSN:0020-1669
1520-510X
DOI:10.1021/acs.inorgchem.5b01857