During Kolbe's electrolytic method, the `pH` of aqueous solution of
salt of acid

Options

A. decreases
B. increases
C. same
D. None of these

Explanation

### Step-by-Step Solution

1. **Understanding Kolbe's Electrolytic Method**:
- Kolbe's electrolytic method involves the electrolysis of an aqueous solution of a salt of a carboxylic acid, typically potassium acetate (CH3COOK).

2. **Ionization of the Salt**:
- When potassium acetate is dissolved in water, it dissociates into potassium ions (K⁺) and acetate ions (CH3COO⁻):
\[ 2 \text{CH}_3\text{COOK} \rightarrow 2 \text{CH}_3\text{COO}^- + 2 \text{K}^+ \]

3. **Electrolysis Process**:
- At the anode, acetate ions (CH3COO⁻) undergo oxidation, leading to the formation of ethane (C2H6) and carbon dioxide (CO2):
\[ 2 \text{CH}_3\text{COO}^- \rightarrow \text{C}_2\text{H}_6 + 2 \text{CO}_2 + 2 \text{e}^- \]
- At the cathode, hydrogen ions (H⁺) are reduced to form hydrogen gas (H2):
\[ 2 \text{H}^+ + 2 \text{e}^- \rightarrow \text{H}_2 \]

4. **Formation of Hydroxide Ions**:
- The presence of water in the solution also leads to the formation of hydroxide ions (OH⁻):
\[ 2 \text{H}_2\text{O} \rightarrow 2 \text{OH}^- + 2 \text{H}^+ \]
- Since H⁺ ions are being consumed at the cathode, the concentration of OH⁻ ions increases.

5. **Effect on pH**:
- The increase in OH⁻ concentration results in an increase in the pH of the solution. This is because pH is inversely related to the concentration of H⁺ ions. As the concentration of OH⁻ increases, the solution becomes more basic (alkaline).

6. **Conclusion**:
- Therefore, during Kolbe's electrolytic method, the pH of the aqueous solution of the salt of the acid increases due to the formation of hydroxide ions (OH⁻) and the reduction of hydrogen ions (H⁺).

### Final Answer:
The pH of the aqueous solution of the salt of acid increases during Kolbe's electrolytic method.

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