Original scientific paper

Kinetics and Mechanism of Reduction of 4(p-Dimethylamino)-Benzylidene-3-Methyl-1-Phenyl-2-Pyrazolin-5-one by Bisulphite Ions in Aqueous Ethanolic Media

M. M. Girgis ; Chemistry Department, Faculty of Science, Assiut University, Assiut, Egypt
R. M. Hassan ; Chemistry Department, Faculty of Science, Assiut University, Assiut, Egypt
Z. H. Khalil ; Chemistry Department, Faculty of Science, Assiut University, Assiut, Egypt

Abstract

The kinetics of the title reduction studied in aqueous ethanolic
media spectrophotometrically. The effect of hydrogen ion concentration on the reduction rate was investigated in buffer solutions at constant ionic strength of 1.0. The reaction was found to be of the first order in both reactants and inverse first order with respect to the hydrogen ion. The rate of the reaction decreased with increasing ethanol as well as hydrogen ion concentrations. Pseudo-first-order rate constant, kob was obtained by monitoring the disappearance of the [dye]. Activation parameters have been evaluated and a tentative reaction mechanism was discussed.

Keywords

Hrčak ID:

176395

URI

https://hrcak.srce.hr/176395

Publication date:

23.12.1987.

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