Effects of Ce{sup 4+}/sulfato complex formation in the Belousov-Zhabotinskii reaction: ESR studies of malonyl radical formation

Journal Article · Thu Apr 02 04:00:00 EST 1992 · Journal of Physical Chemistry

DOI:https://doi.org/10.1021/j100186a054· OSTI ID:263823

Foersterling, H D ^[1]; Stuk, L ^[2]

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1. Philipps-Universitat Marburg, Marburg (Germany)
2. Univ. of Texas, Austin, TX (United States)

The authors investigated the effects of the formation of sulfato complexes from Ce{sup 4+} and H{sub 2}SO{sub 4} on the oxidation of malonic acid (MA) by Ce{sup 4+} in the Belousov-Zhabotinskii (BZ) reaction. The authors found from measuring malonyl radical concentrations in an ESR flow experiment that the rate of formation of sulfato complexes is very fast compared to the rate of the MA/Ce{sup 4+} reaction. This result is important in the theory of the BZ reaction; there is no difference in the reaction rate whether Ce{sup 4+} is freshly produced in the autocatalytic cycle or it is introduced in the sulfato-complexed form. Moreover, the authors did absolute calibrations of the malonyl radical concentrations by using Mn{sup 2+} and 3-carbamoyl-PROXYL as calibration standards. From these concentrations the authors calculated malonyl radical self-decay rates of 4.2 x 10{sup 8} M{sup -1}s{sup -1} in 1 M H{sub 2}SO{sub 4} and 1.5 x 10{sup 9} M{sup -1} s{sup -1} in 2 M HClO{sub 4-}. 23 refs., 6 figs., 5 tabs.

• Sponsoring Organization: USDOE
• OSTI ID: 263823
• Journal Information: Journal of Physical Chemistry, Journal Name: Journal of Physical Chemistry Journal Issue: 7 Vol. 96; ISSN JPCHAX; ISSN 0022-3654
• Country of Publication: United States
• Language: English

Related Subjects

40 CHEMISTRY
CERIUM COMPLEXES
CHEMICAL REACTION KINETICS
ELECTRON SPIN RESONANCE
MALONIC ACID
OXIDATION
RADICALS