Demonstration Procedures

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Reaction of Potassium Chlorate and Sucrose

Procedure

  1. Place a watchglass on a fireproof fiberglass pad.

  2. Very carefully mix 12 grams of KClO3 and 4 grams of sucrose.

  3. Add 1 drop of concentrated sulfuric acid to the mix and step back.

  4. Reaction starts slowly, then bursts into flame with lots of smoke.

  5. Wait for applause.
Note: For this demo to work best, the sucrose and the potassium chromate have to have been ground to a very fine powder with a mortar and pestle. Do this individually before mixing the chemicals.

Note: Do not do this demo in a room without lots of ventilation.

Reactions

The stoichiometry of the reaction is not known. It has been reported that chloric acid (ClO3) is formed when KClO3 and H2SO4 are mixed and that chloric acid decomposes organic substances very rapidly, often with inflammation.