(1) Department of Chemistry, University of Allahabad, Allahabad, 211002, India
Abstract:
Kinetics and mechanism of the Os(VIII) catalysed oxidation of crotonic acid (CA) by KBrO3 in alkaline medium have been investigated. Zero order dependence in [KBrO3] was observed, while first order with respect to CA in its lower concentration range tends to zero order at its higher concentration range. The order in [Os(VIII)] was found to be unity and a positive effect of [OH−] was observed. Variation of the ionic strength (μ) and dielectric constant of the medium and addition of Hg(OAc)2 (used as Br− scavenger) had an insignificant effect on the rate of reaction. Thermodynamic parameters have also been calculated and reported. A suitable mechanism consistent with the observed kinetic results has been suggested and the related rate law deduced.