Chlorination of `CH_4` in sunlight involves

Options

A. Homolytic cleavage
B. Heterolytic cleavage
C. Carbocation
D. carbanion

Explanation

**Step-by-Step Solution:**

1. **Understanding the Reaction**: The chlorination of methane (CH₄) in the presence of sunlight is a free radical substitution reaction. This process involves the substitution of one hydrogen atom in methane with a chlorine atom.

2. **Initiation Step**: The reaction begins with the initiation step, where chlorine molecules (Cl₂) undergo homolytic cleavage due to the energy provided by sunlight (HNU). This results in the formation of two chlorine radicals (Cl•):
\[ \text{Cl}_2 \xrightarrow{\text{sunlight}} 2 \text{Cl}• \]

3. **Propagation Steps**: The chlorine radical (Cl•) then reacts with methane (CH₄) in a propagation step. The chlorine radical abstracts a hydrogen atom from methane, forming chloromethane (CH₃Cl) and a methyl radical (CH₃•):
\[ \text{Cl}• + \text{CH}_4 \rightarrow \text{CH}_3\text{Cl} + \text{H}• \]
The methyl radical (CH₃•) is also a reactive species and can further react with another chlorine molecule:
\[ \text{CH}_3• + \text{Cl}_2 \rightarrow \text{CH}_3\text{Cl} + \text{Cl}• \]
This process continues, leading to the formation of more chloromethane and chlorine radicals.

4. **Termination Step**: Eventually, the reaction will reach a termination step where two radicals combine to form a stable product, thus stopping the reaction. For example:
\[ \text{CH}_3• + \text{CH}_3• \rightarrow \text{C}_2\text{H}_6 \]
or
\[ \text{Cl}• + \text{Cl}• \rightarrow \text{Cl}_2 \]

5. **Conclusion**: The chlorination of CH₄ in sunlight primarily involves homolytic cleavage, as the chlorine bond breaks to form radicals. Heterolytic cleavage, carbocations, and carbanions are not involved in this reaction.

**Final Answer**: The chlorination of CH₄ in sunlight involves **homolytic cleavage**.

---