Chlorination of alkanes is a photochemical process. It is initiated by the process of

Options

A. heterolysis
B. homolysis
C. pyrolysis
D. hydrolysis

Explanation

**Step-by-Step Solution:**

1. **Understanding the Reaction**: The chlorination of alkanes is a chemical process where chlorine (Cl2) reacts with alkanes (hydrocarbons) to form alkyl chlorides. This reaction is classified as a photochemical process because it requires light (sunlight) to initiate.

2. **Identifying the Type of Reaction**: The chlorination of alkanes is a free radical substitution reaction. In this type of reaction, free radicals are involved, which are highly reactive species that contain unpaired electrons.

3. **Formation of Chlorine Free Radicals**: The initiation of the chlorination reaction occurs through the formation of chlorine free radicals. When chlorine gas (Cl2) is exposed to sunlight, the bond between the two chlorine atoms breaks, resulting in the formation of two chlorine free radicals (Cl•).

4. **Bond Cleavage**: The bond cleavage that leads to the formation of free radicals is called homolysis. In homolysis, the bond breaks evenly, and each atom involved in the bond takes away one of the shared electrons, resulting in the formation of two radicals.

5. **Conclusion**: Therefore, the initiation process for the chlorination of alkanes is homolysis of the chlorine-chlorine bond, which produces chlorine free radicals that can then react with alkanes.

**Final Answer**: The initiation of the chlorination of alkanes is through the process of homolysis.

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