kinetics and mechanistic study of oxidation of 4-hydroxy benzaldehyde by alkaline hexacyanoferrate (iii)

The kinetics of oxidation of 4-hydroxy benzaldehyde by hexacyanoferrate(III) in aqueous alkaline medium was studied. The first order dependence on concentration of hexacyanoferrate (III) and fractional order dependence on both 4-hydroxy benzaldehyde and alkali is supported by the derived rate law. A retarding effect was observed by one of the products hexacyanoferrate(II). Increasing ionic strength and dielectric constant of the medium increased the rate of the reaction. The effect of temperature on the rate of reaction has also been studied and activation parameters have been evaluated. A mechanism based on the experimental results is elucidated.