One reactant is broken down into two or more products

This process is called a decomposition reaction. In a decomposition reaction, a single reactant molecule is broken down into two or more smaller product molecules. This reaction can occur through various mechanisms, such as thermal decomposition, electrolysis, or photochemical decomposition. Some examples of decomposition reactions include the breakdown of hydrogen peroxide into water and oxygen gas, the decomposition of limestone into calcium oxide and carbon dioxide, and the decomposition of water into hydrogen gas and oxygen gas under the influence of electricity.