Which of the following salts undergoes hydrolysis ?

Options

A. `K_2SO_4`
B. `KCl`
C. `NaNO_3`
D. `CH_3COONa`

Answer

To determine which of the given salts undergo hydrolysis, we need to analyze each salt based on the nature of its constituent acid and base. Hydrolysis occurs when a salt is formed from a weak acid and a strong base or a strong acid and a weak base. Salts formed from strong acids and strong bases do not undergo hydrolysis.

Let's evaluate each option step by step:

### Step 1: Identify the salts
We have the following salts to analyze:
1. K2SO4
2. KCl
3. NaNO3
4. CH3COONa

### Step 2: Analyze each salt
1. **K2SO4**:
- **Constituent Acid**: H2SO4 (sulfuric acid) - strong acid
- **Constituent Base**: KOH (potassium hydroxide) - strong base
- **Conclusion**: Strong acid + strong base → No hydrolysis.

2. **KCl**:
- **Constituent Acid**: HCl (hydrochloric acid) - strong acid
- **Constituent Base**: KOH (potassium hydroxide) - strong base
- **Conclusion**: Strong acid + strong base → No hydrolysis.

3. **NaNO3**:
- **Constituent Acid**: HNO3 (nitric acid) - strong acid
- **Constituent Base**: NaOH (sodium hydroxide) - strong base
- **Conclusion**: Strong acid + strong base → No hydrolysis.

4. **CH3COONa**:
- **Constituent Acid**: CH3COOH (acetic acid) - weak acid
- **Constituent Base**: NaOH (sodium hydroxide) - strong base
- **Conclusion**: Weak acid + strong base → Hydrolysis occurs.

### Step 3: Final Conclusion
Among the given salts, only **CH3COONa** (sodium acetate) undergoes hydrolysis.

### Summary of the Answer:
The salt that undergoes hydrolysis is **CH3COONa**.

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