The decomposition of potassium chlorate KClO3 is a thermal decomposition reaction, which means it breaks down into simpler substances when heated. The balanced chemical equation for this reaction is:2 KClO3 s 2 KCl s + 3 O2 g When potassium chlorate is heated, it decomposes into potassium chloride KCl and oxygen gas O2 . In this reaction, 2 moles of potassium chlorate produce 2 moles of potassium chloride and 3 moles of oxygen gas.