Give one example for the following:

Photodecomposition

Decomposition Reaction :

1. A reaction in which a substance is broken down into two or simpler substances is called a decomposition reaction.
2. The reaction can take place in the presence of heat, light, or electricity.

Photo-decomposition:

When a decomposition reaction takes place in the presence of light, it is called photo-decomposition

Example:

When hydrogen iodide$\left(\mathrm{HI}\right)$ is exposed to sunlight, it gets decomposed into hydrogen$\left({\mathrm{H}}_2\right)$ and iodine$\left({\mathrm{I}}_2\right)$.

The chemical equation can be written as,

$$\begin{gathered} 2\mathrm{HI}\left(\mathrm{g}\right)\stackrel{\mathrm{light}}{\to }{\mathrm{H}}_2\left(\mathrm{g}\right)+{\mathrm{I}}_2\left(\mathrm{g}\right) \\ \mathrm{Hydrogen}\mathrm{Hydrogen}\mathrm{Iodine} \\ \mathrm{iodide} \end{gathered}$$