Which of the following salts undergoes hydrolysis ?

Options

A. `CH_3COONa`
B. `KNO_3`
C. `NaCI`
D. `K_2SO_4`

Answer

To determine which of the given salts undergo hydrolysis, we need to analyze each salt based on the strength of the acids and bases from which they are derived. Hydrolysis occurs when a salt reacts with water to produce an acidic or basic solution. Here’s a step-by-step breakdown of the solution:

### Step 1: Identify the Salts
The salts given in the question are:
1. Sodium Acetate (CH3COONa)
2. Potassium Nitrate (KNO3)
3. Sodium Chloride (NaCl)
4. Potassium Sulfate (K2SO4)

### Step 2: Analyze Each Salt
**1. Sodium Acetate (CH3COONa)**
- Derived from Acetic Acid (CH3COOH) and Sodium Hydroxide (NaOH).
- Acetic Acid is a weak acid, and Sodium Hydroxide is a strong base.
- The conjugate base of the weak acid (CH3COO-) will be strong.
- Therefore, Sodium Acetate will undergo hydrolysis:
\[ CH3COO^- + H2O \rightleftharpoons CH3COOH + OH^- \]

**2. Potassium Nitrate (KNO3)**
- Derived from Nitric Acid (HNO3) and Potassium Hydroxide (KOH).
- Both Nitric Acid and Potassium Hydroxide are strong.
- The conjugate acid (HNO3) and conjugate base (NO3-) are both weak.
- Therefore, KNO3 will not undergo hydrolysis.

**3. Sodium Chloride (NaCl)**
- Derived from Hydrochloric Acid (HCl) and Sodium Hydroxide (NaOH).
- Both HCl and NaOH are strong.
- The conjugate acid (HCl) and conjugate base (Cl-) are both weak.
- Therefore, NaCl will not undergo hydrolysis.

**4. Potassium Sulfate (K2SO4)**
- Derived from Sulfuric Acid (H2SO4) and Potassium Hydroxide (KOH).
- Both Sulfuric Acid and Potassium Hydroxide are strong.
- The conjugate acid (H2SO4) and conjugate base (SO4^2-) are both weak.
- Therefore, K2SO4 will not undergo hydrolysis.

### Step 3: Conclusion
Only Sodium Acetate (CH3COONa) undergoes hydrolysis because it is derived from a weak acid and a strong base, resulting in a strong conjugate base that can react with water.

### Final Answer
**Sodium Acetate (CH3COONa) undergoes hydrolysis.**