Is There a Safe Chemistry Clock Experiment for Kids Involving Only Water?

[cst38]

I would like to do a chemistry expermient for kids. I would like to perform the chemistry clock experiment with harmless materials. Does anyone know if there is a version of the chemistry clock experiement where you simply add water to a solution to initiate the color change reaction? Thanks in advance for your help.

 

[LoneDragon]

Try looking at Belousov-Zhabotinsky, Bray-Liebhafsky reaction, Briggs-Rauscher reaction, and the Iodine clock reactions all contained in Wikipedia. Science supply sites might have the products or kits for one of these reactions, though some may be difficult to setup properly, and some are noticeably colorful. In liew of setup, there are pictures and videos of some of these reactions on the web too.