Question

What is chlorination reaction?

Answer 1

1. Chlorination is the chemical reaction in which Chlorine is introduced to a molecule and it is a free radical substitution reaction.
2. It is a kind of halogenation reaction.
3. An example of chlorination is the chlorination of methane in presence of sunlight.
4. This reaction is a three-step mechanism that involves Chain initiation, propagation step, and termination step.
5. Chain initiating step: The $\mathrm{Cl}-\mathrm{Cl}$ bond of Chlorine undergoes cleavage homolytic cleavage and generates chlorine radicals when exposed to sunlight.
   

1. Propagation step: Chlorine radical reacts with Methyl radical and abstracts the Hydron from it forming the methyl radical. Now the Methyl radical will react with the Chlorine atom and form Chloromethane. These steps keep repeating till the termination occurs.

1. Termination Step: When a Chlorine radical reacts with another Chlorine radical forming ${\mathrm{Cl}}_2$ results in termination, Chlorine radical can also react with methyl radical forming Chloromethane as a product. One more possibility can happen is the combination of two methyl radicals forming Ethane.