Coal from sugar

Half fill a 200ml beaker with sugar.

Place the beaker with the sugar onto a heat-proof mat in a fume cupboard. Pour enough concentrated sulfuric acid to cover the surface of the sugar.

The colour of the sugar crystals starts to change.

The sugar crystals turn black. The reaction is extremely exothermic. Plumes of steam rise quickly from the rising hot column of carbon. Click to see a 120kb video.