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ABSTRACT Kinetic studies on the Belousov-Zhabotinsky (BZ) system with various metal ions as catalysts have been carried out for a long time, but the effect of counteranions associated with the metal ion solution used as the catalyst in the BZ reaction has not been explored. Thus, we have chosen some metal salts as catalysts having the metal ion (Mn n+) but with various anions to study the role of different anionic moieties of catalyst on the oscillatory behavior of the resorcinol-based BZ reaction system. It is found that organic-type anionic moieties marginalize the role of organic substrates in the reaction system. On the other hand, the inorganic counterions of the catalyst show salting out effects, thereby increasing the ionic strength, which affects the mobility (diffusion) of the ions in our system performed under batch conditions. [ABSTRACT FROM AUTHOR]

The present investigation pertains to the kinetic study on bromate-driven and manganese ion catalyzed Belousov-Zhabotinsky oscillatory chemical reaction having catechol (1,2-dihydroxybenzene) as the organic substrate in aqueous acid media at 30 ± 0.1oC under stirred conditions. Although some polyphenols as chemical oscillators are known in the literature but the role of catechol has been marginalized. The reaction system with catechol shows long-time series of periodic as well as aperiodic oscillations, which were monitored potentiometrically in the oxidation reduction potential (ORP) mode under batch conditions. The various oscillatory parameters such as induction time ( tin), time period ( tp), amplitude ( A), and number of oscillations ( N) were obtained by drawing a plot between redox potential (mV) versus time (s). It is found that the oscillatory parameters of the system vary with the concentration of the reacting species. The reaction system was also studied in different aqueous acid media, but the detailed studies with respect to experimental parameters have been made in aqueous sulfuric acid medium as it showed a broad oscillatory window and better oscillatory characteristics. Moreover, the oscillatory parameters in general and induction time in particular vary significantly with temperature (15 to 45 ± 0.1oC). The activation parameters of the system have also been calculated. The oscillatory behavior of the reaction system was also confirmed spectrophotometrically. © 2012 Wiley Periodicals, Inc. Int J Chem Kinet 45: 141-151, 2013 [ABSTRACT FROM AUTHOR]