Seriously… Watch this, watch this, watch this…

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What you are watching is called The Briggs-Rauscher reaction, demoed by “the guy who literally wrote the book on chemistry demos: University of Wisconsin-Madison Chemistry Professor and 2012 ACS President Bassam Shakhashiri, author of the popular “Chemical Demonstrations” textbooks.”

Via Eric Lagally.

p.s. Here are the recipes:

– Solution A:
Add 43 g potassium iodate (KIO₃) to ~800 mL distilled water. Stir in 4.5 mL sulfuric acid (H₂SO₄). Continue stirring until the potassium iodate is dissolved. Dilute to 1 L. 

– Solution B:
Add 15.6 g malonic acid (HOOCCH₂COOH) and 3.4 g manganese sulfate monohydrate (MnSO₄ . H₂O) to ~800 mL distilled water. Add 4 g of vitex starch. Stir until dissolved. Dilute to 1 L. 

– Solution C:
Dilute 400 mL of 30% hydrogen peroxide (H₂O₂) to 1 L.

Procedure

Place the stirring bar into the large beaker.
Pour 300 mL each of solutions A and B into the beaker.
Turn on the stirring plate. Adjust the speed to produce a large vortex.
Add 300 mL of solution C into the beaker. Be sure to add solution C after mixing solutions A + B or else the demonstration will not work. Enjoy!

Notes

This demonstration evolves iodine. Wear safety goggles and gloves and perform the demonstration in a well-ventilated room, preferably under a ventilation hood. Use care when preparing the solutions, as the chemicals include strong irritants and oxidizing agents.

Clean Up

Neutralize the iodine by reducing it to iodide. Add ~10 g sodium thiosulfate to the mixture. Stir until the mixture becomes colorless. The reaction between iodine and thiosulfate is exothermic and the mixture may be hot. Once cool, the neutralized mixture may be washed down the drain with water.

From chemistry.about.com.