| MadSci Network: Chemistry |
In the BZ reactions, the color changes as the oxidation state of the catalyst changes. If Cerium is used, then the Ce(IV) is yellow and the Ce(III) is colorless. Ferroin is sometimes used instead because it provides a dramatic change in color from red (reduced ) to blue (oxidized). You can find more information in the following sources: Epstein, I. R.; Pojman, J. A. An Introduction to Nonlinear Chemical Dynamics: Oscillations, Waves, Patterns and Chaos; Oxford University Press: New York, 1998. Epstein, I. R.; Kustin, K.; De Kepper, P.; Orbán, M. "Oscillating Chemical Reactions,"Scientific American 1983, 248, 112-123. Shakhashiri, B. Z. Chemical Demonstrations: A Handbook for Teachers. Volume 2; University of Wisconsin Press: Madison, 1985. Pojman, J. A.; Craven, R.; Leard, D. "Oscillating Reactions and Traveling Waves in the Physical Chemistry Lab,"J. Chem. Ed. 1994, 71, 84-90. The March issue of the Journal of Chemical Education in 1989. Our www site: http://www.pojman.com
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