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How do decomposition reactions break compounds into simpler substances?
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chemical reaction
Log burning in a fire. Burning wood is an example of a chemical reaction in which wood in the presence of heat and oxygen is transformed into carbon dioxide, water vapor, and ash.
Decomposition reactions are chemical processes in which a single compound breaks down into two or more simpler substances. These reactions typically require an input of energy to overcome the activation energy—the minimum energy threshold required to initiate a chemical transformation.12
Common methods used to drive these reactions include:
- Heat (Thermal Decomposition): Applying heat can break the bonds within a compound. For example, heating mercury oxide (HgO) produces mercury metal and oxygen gas.1
- Electrolysis: Passing an electric current through a substance can force it to decompose. An example is the electrolysis of molten sodium chloride (NaCl) to produce sodium and chlorine gas.1
- Hydrolysis: This is a specific type of decomposition involving water as a reactant. In biological systems, enzymes act as catalysts to facilitate the breakdown of complex molecules like proteins, fats, and starches into simpler, assimilable forms.3