Ramdon, Dwight C.; Dixon, Donovan A.; Dasgupta, Tara P
Author Affiliation, Ana.
Department of Chemistry
Mechanistic study of the reactions of the chromium(VI) ion in aqueous sulfite solution
Inorganic Reaction Mechanisms
Date of Publication
The kinetics of the reactions between chromium(VI) and sulfer(IV) ions has been extensively studied by stopped-flow spectrophotometry. Studies were conducted in the presence and absence of oxygen in aqueous solution at 25°C, at an ionic strength of 0.5 M (NaC1O4) over the ranges of, 5 x 10-3 £ [SIV]T £ 90 x 10-3 M and 3.3 £ pH £ 5.3. Reactions were conducted in acetate and phosphate-citrate buffers and the experimental rate constant, kobs, were found to be independent of both acetate and oxygen concentrations of phosphate-citrate, [H+] and the total sulfite, [SIV]T, results in an increase in the values of kobs. An overall mechanism is discussed, which takes into consideration the reactions of all the various species that are present in aqueous solution under the experimental conditions employed in the study.....