Mix sugar and potassium chlorate in a test tube. Only small quantities, as pictured on the right, should be used. Use the granulated sugar and not the powdered sugar.

Place the test tube in sand to protect the container from the extreme heat generated.

Place one drop of concentrated sulfuric acid on to the mixture.

When sulfuric acid is introduced heat is created which decomposes potassium chlorate to produce oxygen according to the equation below.
2KClO_3(s) + heat —> 2KCl_(s) + 3O_2(g)

Some of the products of the reaction are shown on the right. Black pieces of carbon can be seen inside the test tube. Other products include carbon dioxide, water and of course heat.

Equipment:

- concentrated sulfuric acid
- large test tube.
- 9.00 grams sugar
- 9.00 grams KClO₃
- dropper
- plastic container with sand.

Mix the sugar and potassium chlorate in a test tube. Use the granulated sugar and not the powdered sugar.
Place the test tube with the mixture in the sand. Drop one drop of sulfuric acid in the test tube to initiate the reaction.

Safety equipment - lab coat and goggles. This demonstration must be performed outdoors or in a well ventilated fume cupboard.

Theory.

We suspect that chloric acid (HClO₃) is formed when potassium chlorate (KClO₃ ) and sulfuric acid (H₂SO₄ ) are mixed. Chloric acid rapidly decomposes organic material, such as sugar, with the release of enormous amounts of heat energy.
The exothermic reaction proceeds according to the equation below with the release of 2029 kJ of energy per mol of sugar reacting.
C₁₂H₂₂O_11(s) + 8KClO_3(s) => 12CO_2(g) + 11H₂O_(g) + 8KCl_(s)

The heat released from the above reaction quickly fuels a second reaction given by the equation below.
C₁₂H₂₂O_11(s) => 12C_(s) + 11H₂O_(g) .

This reaction gives off even more energy to the tune of 429 kJ for every mol of sugar that reacts. The solid carbon (graphite) formed is visible after the reaction has ceased.