Studies on the Reduction of Potassium Permanganate by Oxalic Acid and its Homologues

Reduction of potassium permanganate by oxalic, malonic, and succinic amide has been studied and the rate constants have been determined. The reaction is found to be autocatalytic and is mainly governed by the dissociation constants of these acids. The dissociation constants of oxalic acid (K₁= 3.8X10^-2,K₂=4.9 X10^-5). malonic acid (K₁ =1.61 x10^-3, K₂= 2.1 x10^-6), and succinic acid (K₁ = 6.63 X10^-5, K₂= 2.1 X10^-6) indicate the reduction taking place by such carboxylic acids, dissociation constants of which range between 10^-2 and 10^-3. In the case of succinic acid, the reducing power is very low. A-mechanism of these reactions has been suggested.