Which salt cannot be cannot be hydrolysed ?

Options

A. Potassium nitrate
B. Potassium cyanide
C. Potassium succinate
D. Potassium carbonate

Answer

To determine which salt cannot be hydrolyzed, we need to understand the concept of hydrolysis in relation to the nature of the salts formed from acids and bases.

### Step-by-Step Solution:

1. **Understand Hydrolysis**: Hydrolysis is the reaction of a salt with water, resulting in the formation of an acid and a base. This typically occurs with salts derived from weak acids or weak bases.

2. **Identify Types of Salts**: Salts can be categorized based on the strength of the acid and base from which they are formed:
- **Strong Acid + Strong Base**: These salts are neutral and do not undergo hydrolysis.
- **Strong Acid + Weak Base**: These salts can hydrolyze, producing acidic solutions.
- **Weak Acid + Strong Base**: These salts can hydrolyze, producing basic solutions.
- **Weak Acid + Weak Base**: These salts can hydrolyze, producing both acidic and basic solutions.

3. **Identify the Given Salts**:
- **Potassium Nitrate (KNO3)**: Formed from nitric acid (strong acid) and potassium hydroxide (strong base).
- **Potassium Cyanide (KCN)**: Formed from hydrocyanic acid (weak acid) and potassium hydroxide (strong base).
- **Potassium Succinate**: Formed from succinic acid (weak acid) and potassium hydroxide (strong base).
- **Potassium Carbonate (K2CO3)**: Formed from carbonic acid (weak acid) and potassium hydroxide (strong base).

4. **Analyze Each Salt**:
- **KNO3**: Since it is formed from a strong acid and a strong base, it is neutral and cannot undergo hydrolysis.
- **KCN**: Can undergo hydrolysis due to the weak acid.
- **Potassium Succinate**: Can undergo hydrolysis due to the weak acid.
- **K2CO3**: Can undergo hydrolysis due to the weak acid.

5. **Conclusion**: The only salt that cannot be hydrolyzed is **Potassium Nitrate (KNO3)**, as it is formed from a strong acid and a strong base.

### Final Answer:
**Potassium Nitrate (KNO3)** cannot be hydrolyzed.