Event Title

Oscillating Chemical Reactions

Graduation Year

2015

Location

Room E105, Center for Natural Sciences, Illinois Wesleyan University

Start Date

18-4-2015 11:00 AM

End Date

18-4-2015 12:00 PM

Description

Briggs-Rauscher reaction and Belousov-Zhabotinsky reaction are two well-known, but still incompletely understood, nonlinear oscillating chemical reactions which are characterized by cyclic color changes. We have discovered that, in the absence of stirring, the time period of these nonlinear oscillations is affected by the depth of the solution in a container, and not just upon the specific chemistry, for example the concentrations of various reagents and reaction temperature. This makes it clear that macroscopic diffusion, over length scales that are comparable to the dimensions of the container, play an important role in these oscillations. We have therefore extended our study to explore the dynamics of two diffusion-coupled chemical oscillators, and look for possible novel and interesting modes of coupled nonlinear chemical oscillations. This is done by machining two small shallow wells in a thick Teflon sheet, connected by a narrow channel. The strength of diffusional coupling decreases as the length of the coupling channel increases. Reactions, for varying channel lengths, and chemistry, were recorded by a video camera, and the resulting videos were exported to Mathematica for an RGB analysis of various parts of the reaction chamber. The result of the study will be presented.

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Apr 18th, 11:00 AM Apr 18th, 12:00 PM

Oscillating Chemical Reactions

Room E105, Center for Natural Sciences, Illinois Wesleyan University

Briggs-Rauscher reaction and Belousov-Zhabotinsky reaction are two well-known, but still incompletely understood, nonlinear oscillating chemical reactions which are characterized by cyclic color changes. We have discovered that, in the absence of stirring, the time period of these nonlinear oscillations is affected by the depth of the solution in a container, and not just upon the specific chemistry, for example the concentrations of various reagents and reaction temperature. This makes it clear that macroscopic diffusion, over length scales that are comparable to the dimensions of the container, play an important role in these oscillations. We have therefore extended our study to explore the dynamics of two diffusion-coupled chemical oscillators, and look for possible novel and interesting modes of coupled nonlinear chemical oscillations. This is done by machining two small shallow wells in a thick Teflon sheet, connected by a narrow channel. The strength of diffusional coupling decreases as the length of the coupling channel increases. Reactions, for varying channel lengths, and chemistry, were recorded by a video camera, and the resulting videos were exported to Mathematica for an RGB analysis of various parts of the reaction chamber. The result of the study will be presented.