All combustion reactions ... extremely exothermic chemical reactions. The first 'reaction' that we tried for our hand warmer involved dissolving potassium carbonate (K 2 CO 3) in water.

A simple demonstration of how a precipitate is evidence of a chemical reaction taking place is performed by mixing solutions of calcium chloride and sodium carbonate to form the precipitate calcium ...

This is consolidated by using the thermal decomposition of calcium carbonate. Introduce the concept of conservation of mass in chemical reactions ... in relation to the combustion of hydrocarbons.

This is consolidated by using the thermal decomposition of calcium carbonate. Introduce the concept of conservation of mass in chemical reactions ... in relation to the combustion of hydrocarbons.