The kinetics of oxidation of L-ascorbic acid by potassium chromate was studied as a function of pH, L-ascorbic acid concentration and temperature using the spectrophotometric technique. The rate of reaction is first order with respect to the concentration of each reactant and increases as [H+] increases. The kinetic data indicate involvement of the monoprotonated ascorbate species (HA-) in the redox process. A mechanism involving the formation of chromium (VI)- ascorbate intermediate is a rate-determining step followed by a redox step was suggested. The activation enthalpy and activation entropy changes for the reaction have been calculated to be ΔH*= 69 kJmol-1 and ΔS*= -209 JK-1 mol-1, respectively.
MANSOUR, M. (2010). KINETICS AND MECHANISM OF OXIDATION OF L-ASCORBIC ACID BY CHROMIUM (VI). Al-Azhar Bulletin of Science, 21(Issue 1-A), 189-198. doi: 10.21608/absb.2010.7344
MLA
MOHAMED A. MANSOUR. "KINETICS AND MECHANISM OF OXIDATION OF L-ASCORBIC ACID BY CHROMIUM (VI)". Al-Azhar Bulletin of Science, 21, Issue 1-A, 2010, 189-198. doi: 10.21608/absb.2010.7344
HARVARD
MANSOUR, M. (2010). 'KINETICS AND MECHANISM OF OXIDATION OF L-ASCORBIC ACID BY CHROMIUM (VI)', Al-Azhar Bulletin of Science, 21(Issue 1-A), pp. 189-198. doi: 10.21608/absb.2010.7344
VANCOUVER
MANSOUR, M. KINETICS AND MECHANISM OF OXIDATION OF L-ASCORBIC ACID BY CHROMIUM (VI). Al-Azhar Bulletin of Science, 2010; 21(Issue 1-A): 189-198. doi: 10.21608/absb.2010.7344
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