Abstract

The kinetics of silver (I) catalyzed oxidation of l-ascorbic acid (H₂A) by peroxodiphosfate (PDP) in acetate buffers has been studied. Triple distilled water was employed to eliminate suspected trace metal-ion catalysis of Cu (II) or Fe (III). The kinetics was monitored ceremetrically and the rate has been found to be independent of substrate concentration. A plausible reaction mechanism has been suggested. Results were analysed graphically in view of complex rate equation. The role of the catalyst has been via Ag^I/Ag^II redox cycle, Ag (II) confirming the presence of by the addition of 2,2’-bipyridyl where brown-orange color of Ag^I(bipy)₂ complex of transient life time was observed.

Keywords: Catalysis, kinetics, L-ascorbic acid, mechanism, silver (I), peroxodiphosfate.