POLAROGRAPHIC STUDIES ON THE KINETICS OF THE ELECTRODE-REACTION OF 4-BENZOYL-1,5 DIPHENYL PYRAZOLE-3-CARBOXYLIC ACID

The polarographic behavior of 4-Benzoyl-1,5 diphenyl pyrazole-3- Carbo xylic acid (BDPPCA) in aqueous ethanol solution (76 % v/v) at 25 degre es C was studied as a function of pH using Mcl buffer solution. One we ll-defined wave was obtained in the pH range of 3.3-5.4. This wave, co rresponding to two electron reduction processes, was irreversible and diffusion controlled. However, in the pH range of 5.4-7.4 a single rev ersible and diffusion-controlled wave involving two electrons resulted . The kinetic parameters (n(a),k(f,h)degrees) were calculated by Koute cky's method. A tentative mechanism was put forward for the reduction process of depolarizer. Furthermore, the effects of different supporti ng electrolytes on the kinetics of the irreversible electrode reaction of BDPPCA were investigated.