Kolbe’s reaction is convenient for the preparation of -

Options

A. Methane
B. Alkanes containing even number of carbon atoms
C. Alkanes containing even as well as odd number of carbon atoms
D. Alkanes containing odd number of carbon atoms

Answer

**Step-by-Step Solution:**

1. **Understanding Kolbe's Reaction**: Kolbe's reaction, also known as Kolbe electrolysis, involves the electrolysis of sodium or potassium salts of carboxylic acids. This reaction is a method for the preparation of alkanes.

2. **Decarboxylative Dimerization**: The key feature of Kolbe's reaction is that it leads to the decarboxylative dimerization of carboxylic acids. When two carboxylate ions are electrolyzed, they can couple together to form a new carbon-carbon bond.

3. **Formation of Radicals**: During the electrolysis, the carboxylate ions (RCOO⁻) lose carbon dioxide (CO₂) and generate free radicals (R•). This occurs in a two-stage radical process where the carboxylate ion is first converted into a radical.

4. **Coupling of Radicals**: The free radicals generated can then couple together to form alkanes. The resulting alkanes will have an even number of carbon atoms, as two radicals combine to form a single alkane molecule.

5. **Example of Products**: For instance, if you start with sodium acetate (CH₃COONa), the Kolbe electrolysis will yield ethane (C₂H₆) as the product. Thus, Kolbe's reaction is particularly convenient for the preparation of symmetrical alkanes.

**Final Answer**: Kolbe’s reaction is convenient for the preparation of alkanes.

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