Which type of chemical reaction involves a substance breaking down into simpler products?

The type of chemical reaction that involves a substance breaking down into simpler products is decomposition. In a decomposition reaction, a single compound undergoes a process that leads to the formation of two or more simpler substances. This often occurs through the application of heat, light, or electricity.

For example, when potassium chlorate (KClO3) is heated, it breaks down into potassium chloride (KCl) and oxygen gas (O2). This reaction illustrates the breakdown of a compound into its component parts, which is the hallmark of a decomposition reaction.

Understanding this reaction type is essential as it contrasts with other types of reactions. In synthesis reactions, for instance, simpler substances combine to form a more complex compound. Double replacement reactions involve the exchange of components between two compounds, while combustion reactions typically involve a substance reacting with oxygen to produce energy, often resulting in products like carbon dioxide and water rather than simple breakdown products.