Question

Write a chemical equation for photodecomposition reaction.

Answer 1

Hint: Photo decomposition Reaction is a chemical reaction in which a compound gets broken down into simple substances under its exposure to light. This reaction is also known as Photolysis or Photodissociation reaction.

Complete step by step answer:
A decomposition reaction is a reaction in which the reactant breaks down into two or more products.
Representation of decomposition reaction:
$AB \to A + B$
In above equation, AB is reactant which breaks down into two products i.e. A and B.
Decomposition of a compound into its components under the presence of light is known as photodecomposition reaction.
The chemical reactions involved are written below:
\[
  2AgCl(s)\,\mathop \to \limits^{sunlight} \,2Ag(s)\, + \,C{l_2}(g) \\
    \\
 \]
In the above reaction, we can see that Silver Chloride under presence of sunlight decomposes to form Silver and Chlorine gas. When silver chloride crystals which are white in colour are kept under sunlight, they turn into grey colour as it loses chlorine gas.
\[2{H_2}{O_2}(l)\,\mathop { \to \,}\limits^{sunlight} \,2{H_2}O(l)\, + \,{O_2}(g)\]
Another example of photodecomposition reaction is decomposition of hydrogen peroxide under the presence of sunlight. Hydrogen peroxide is decomposed to water and oxygen gas.

Note:
Other examples of decomposition reactions are given below:
Thermal Decomposition:
Chemical reactions which are caused by heat are known as Thermal Decomposition Reactions. Example of such type of reaction is given below:
$CuC{O_3}\mathop \to \limits^{heat} \,CuO + C{O_2}$
Electrolytic Decomposition: An electrolytic decomposition reaction is a type of reaction in which the energy is provided in the form of electrical energy which in turn is responsible for decomposition of the compound. Example of such type of reaction is given below:
$2NaCl \to 2Na + C{l_2}$