The degree of hydrolysis of a salt of `W_(A)` and `W_(B)` in its `0.1M` solution is `50%`. If the molarity of the solution is `0.2M`, the percentage hydrolysis of the salt woukd be

Options

A. `25%`
B. `50%`
C. `75%`
D. `100%`

Explanation

To solve the problem, we need to understand the concept of hydrolysis of a salt formed from a weak acid and a weak base. The degree of hydrolysis is the fraction of the salt that undergoes hydrolysis.

### Step-by-Step Solution:

1. **Identify the Given Information:**
- The degree of hydrolysis (α) in a 0.1 M solution is 50%. This means that 50% of the salt hydrolyzes in this concentration.
- The molarity of the new solution is 0.2 M.

2. **Understand the Concept of Degree of Hydrolysis:**
- The degree of hydrolysis (α) is defined as the fraction of the salt that has undergone hydrolysis. In percentage terms, 50% hydrolysis means α = 0.5.

3. **Effect of Concentration on Degree of Hydrolysis:**
- For salts of weak acids and weak bases, the degree of hydrolysis is independent of the concentration of the solution. This means that if the concentration of the solution changes, the degree of hydrolysis remains the same.

4. **Apply the Concept:**
- Since the degree of hydrolysis is independent of concentration for weak acid-weak base salts, the degree of hydrolysis in the 0.2 M solution will also be the same as in the 0.1 M solution.

5. **Conclusion:**
- Therefore, the percentage hydrolysis of the salt in the 0.2 M solution will also be 50%.

### Final Answer:
The percentage hydrolysis of the salt in a 0.2 M solution is **50%**.

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