"Kinetics and Mechanism of Chromate Reduction with Hydrogen Peroxide in" by Douglas A. Vander Griend, Joshua S. Golden et al.
 

Kinetics and Mechanism of Chromate Reduction with Hydrogen Peroxide in Base

ACS Citation

Vander Griend, D. A.; Golden, J. S.; Arrington, C. A. Kinetics and Mechanism of Chromate Reduction with Hydrogen Peroxide in Base. Inorg. Chem. 2002, 41, 7042-7048.

Abstract

CrVIO4]2- is reduced to CrV(O2)4]3- by hydrogen peroxide in strongly basic media where the acid dissociation of H2O2 (pKa = 11.65) is appreciable. The reaction is first order in chromium(VI) and inhibited by hydroxide. The hydrogen peroxide dependence is defined by the form of the effective pseudo-first-order rate constant:? keff = H2O2]3/(K1 + K2H2O2] + K3HO2-]) with K1 = 175(43) s·M3, K2 = 403(18) s·M2, and K3 = 1422(34) s·M2. Hydrogen peroxide anion initially attacks chromate, and subsequent equilibrium steps that exchange oxo groups for three peroxo groups precede a rate-determining, one-electron, intramolecular reduction step. CrVIO4]2- is reduced to CrV(O2)4]3- by hydrogen peroxide in strongly basic media where the acid dissociation of H2O2 (pKa = 11.65) is appreciable. The reaction is first order in chromium(VI) and inhibited by hydroxide. The hydrogen peroxide dependence is defined by the form of the effective pseudo-first-order rate constant:? keff = H2O2]3/(K1 + K2H2O2] + K3HO2-]) with K1 = 175(43) s·M3, K2 = 403(18) s·M2, and K3 = 1422(34) s·M2. Hydrogen peroxide anion initially attacks chromate, and subsequent equilibrium steps that exchange oxo groups for three peroxo groups precede a rate-determining, one-electron, intramolecular reduction step.

Source Name

Inorganic Chemistry

Publication Date

1-1-2002

Volume

41

Issue

26

Page(s)

12249-12257

Document Type

Citation

Citation Type

Article

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