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Frerichs GA, Jones J, Huang X, Gebrekidan M, Burch J, Cheng MY, Chen Y. Batch pH Oscillations in the Belousov-Zhabotinsky Reaction. J Phys Chem A 2019; 123:1303-1310. [PMID: 30672706 DOI: 10.1021/acs.jpca.8b11222] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
No single-phase system has been previously reported to give significant pH oscillations in a closed (batch) reactor. We report here sustained pH oscillations in batch for the Belousov-Zhabotinsky reaction using much lower [H+]0 and much higher [BrO3-]0 than in traditional studies of this reaction. In fact, pH oscillations were obtained in the presence of only BrO3-, malonic acid (MA), and Mn2+. The amplitude, frequency, and duration of oscillations tend to depend primarily on the ratio of [BrO3-]0 to [MA]0. A critical part of the proposed mechanism involves the reversible formation of a manganese(III) complex with bromomalonic acid, followed by two-electron oxidation to tartraric acid and Mn2+. Estimates of the corresponding rate constant values for these reactions have been obtained by simulation. It is suggested that the presence of a supercatalytic reaction in H+ may be a sufficient, if not necessary, requirement for the occurrence of pH oscillations in a batch system.
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Affiliation(s)
- Glen A Frerichs
- Department of Chemistry , Westminster College , 501 Westminster Avenue , Fulton , Missouri 65251 , United States
| | - James Jones
- Department of Chemistry , Westminster College , 501 Westminster Avenue , Fulton , Missouri 65251 , United States
| | - Xiaohe Huang
- Department of Chemistry , Westminster College , 501 Westminster Avenue , Fulton , Missouri 65251 , United States
| | - Mulurhab Gebrekidan
- Department of Chemistry , Westminster College , 501 Westminster Avenue , Fulton , Missouri 65251 , United States
| | - Jacob Burch
- Department of Chemistry , Westminster College , 501 Westminster Avenue , Fulton , Missouri 65251 , United States
| | - Mei Yuan Cheng
- Department of Chemistry , Westminster College , 501 Westminster Avenue , Fulton , Missouri 65251 , United States
| | - Yuwei Chen
- Department of Chemistry , Westminster College , 501 Westminster Avenue , Fulton , Missouri 65251 , United States
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