Question

With the help of equations briefly explain the bleaching action of chlorine.

Answer 1

Hint: Chlorine can act as a bleaching agent due to the nascent oxygen it can produce in the reaction with water. Basically, one Cl atom gets oxidised and the other gets reduced when chlorine gas reacts with water.

Complete answer:
Bleaching process involves decolourization of the coloured materials.
Chlorine bleaches by the process of oxidation. It needs moisture for its bleaching action. Chlorine reacts with water to form hydrochloric and hypochlorous acids. Here is the equation:

$\text{C}{{\text{l}}_{\text{2}}}\text{ + }{{\text{H}}_{\text{2}}}\text{O }\xrightarrow{{}}\text{ HCl + HClO}$

Here, we can see that one chlorine atom gets oxidised and the other gets reduced.
Hypochlorous acid has chlorine atom in +1 oxidation state, so it is unstable and it easily dissociates and forms nascent oxygen. The equation is as below.

$\text{HClO }\xrightarrow{{}}\text{ HCl + }\!\![\!\!\text{ O }\!\!]\!\!\text{ }$

Nascent oxygen is a very powerful oxidising agent because it is very unstable. The nascent oxygen is responsible for the bleaching nature of chlorine in presence of water as moisture. Nascent oxygen suggests the oxygen formed during the course of the reaction which is very unstable.
This nascent oxygen will react with coloured material effectively and oxidise it to a compound that is colourless. Thus, it bleaches the material.

Additional Information Nascent oxygen is very reactive and can react with different molecules. It is considered to be toxic to the aerobic life forms because oxygen can be converted into nascent oxygen.
> Bleach is very irritating and corrosive to the skin, lungs, and eyes. As well, it has been known to burn human tissue internally and externally. Poor chlorine, however, is substantially stronger than household breach.

Note: Note that chlorine does not react with the coloured materials to make them colourless, instead it is the nascent oxygen that gets formed during its interaction with moisture that is responsible for the bleaching action.