Electrochemical examination of the pyrocatechol influence on the Bray Liebhafsky reaction after the oscillatory period

Abstract

Thanks to the great sensitivity of oscillating reactions to external perturbations, which primarily refers to different analyte addition, chemical oscillators have become very popular for analytic determination of “reactive” analytes, and thus expand their use to many areas, such as environmental, pharmacy, food science etc. This paper aims at an electrochemical examination of the pyrocatechol (analyte) influence on the Bray-Liebhafsky (BL) reaction after the oscillatory period, precisely after six regular oscillations. Pyrocatechol addition provokes the appearance of one more BL oscillation after the second induction period. For investigated BL system, in a range of pyrocatechol concentrations from 2.7 × 10-6 M to 1.2 × 10-4 M, the period between sixth and seventh oscillations shows linear dependence with added pyrocatechol concentration. The obtained regression equation can be a useful tool for analytical purposes and accordingly, potential determination of unknown pyrocatechol concentration.

Zahvaljujući velikoj osetljivosti oscilatornih reakcija na spoljne perturbatore, koja se prvenstveno odnosi na dodavanje različitih analita, hemijski oscilatori postali su vrlo popularni za analitičko određivanje „reaktivnih“ analita, proširivši svoju primenu na mnoge naučne grane, poput zaštite zivotne sredine, farmacije, nauke o hrani itd. Ovaj rad ima za cilj elektrohemijsko ispitivanje uticaja pirokatehola (analita) na Bray-Liebhafsky (BL) reakciju nakon oscilatornog perioda, odnosno nakon šest pravilnih oscilacija. Dodatak pirokatehola izaziva pojavu još jedne BL oscilacije nakon drugog indukcionog perioda. Za ispitivani BL sistem, u opsegu koncentracija pirokatehola od 2,7 × 10-6 M do 1,2 × 10-4 M, period između šeste i sedme oscilacije pokazuje linearnu zavisnost od koncentracije dodatog pirokatehola. Dobijena kalibraciona jednačina se može koristiti u analitičke svrhe i shodno tome, za potencijalno određivanje nepoznate koncentracije pirokatehola.