Question

Define decomposition reactions.

Answer 1

Step 1: Decomposition reactions

Those reactions in which a reactant splits up into simpler substances are known as decomposition reactions. These reactions are the opposite of combination reactions.

Step 2: Example

An example of a decomposition reaction is given below:

When calcium carbonate is heated, it decomposes to give two new products named calcium oxide and carbon dioxide.

$$\begin{gathered} {\mathrm{CaCO}}_3\left(\mathrm{s}\right)\to \mathrm{CaO}\left(\mathrm{s}\right)+{\mathrm{CO}}_2\left(\mathrm{g}\right) \\ \mathrm{calcium}\mathrm{calcium}\mathrm{carbon}\mathrm{dioxide} \\ \mathrm{carbonate}\mathrm{oxide} \end{gathered}$$