Chemical clock reaction

Hello everyone! I'm 劉俊廷 and I hope you can be impressed by the reaction I described this week!

   Chemical clock reaction, or oscillating reaction, is a type of reaction that the concentration of certain compounds fluctuating over time. Usually, this kind of reaction shows rapid changes in color, and that’s why it’s often used as a magic or demonstrated experiment. Not only is the reaction spectacular, but the studies of the mechanism behind the color change indeed provide us insights into chemical kinetics. What’s more, it even resulted in the emerge of two brand new field—non-equilibrium thermodynamics and non-linear dynamics.

    Examples of chemical clock are quiet rare. Beside the common iodine clock which perhaps everyone has conducted it in high school, there are also BZ reaction, Briggs-Rauscher reaction and Bray-Liebhafsky reaction.

   

   Here are some videos regarding them:

*iodine clock

*BZ reaction

*Briggs-Rauscher reaction

   The mechanism behind these reactions is really complex. To be short, there all exists two reaction pathway—one generates the reactant (or product), and the other depletes the reactant (or product). So that’s why we see the color, which implies the concentration of chemical compounds, changes periodically. To make this blog science popular, I don't want to talk too academic. But anyone who wants to learn more can just contact with me:)