Aqueous solution of which salt will not be hydrolysed?

Options

A. Potassium nitrate
B. Potassium cyanide
C. Potassium formate
D. Potassium acetate

Answer

To determine which aqueous salt will not be hydrolyzed, we need to analyze the hydrolysis of the given salts. Hydrolysis refers to the reaction of a salt with water, which can lead to the formation of an acidic or basic solution depending on the nature of the salt.

### Step-by-Step Solution:

1. **Identify the Salts**: The salts given in the question are:
- Potassium nitrate (KNO3)
- Potassium cyanide (KCN)
- Potassium formate (HCOOK)
- Potassium acetate (CH3COOK)

2. **Understand Hydrolysis**: Hydrolysis occurs when a salt reacts with water to form an acid and a base. The extent of hydrolysis depends on whether the salt is derived from a strong acid and a strong base, a weak acid and a strong base, a strong acid and a weak base, or a weak acid and a weak base.

3. **Analyze Each Salt**:
- **Potassium Nitrate (KNO3)**:
- KNO3 is formed from the strong acid (HNO3) and the strong base (KOH).
- Hydrolysis: KNO3 + H2O → KOH + HNO3
- Since both components are strong, KNO3 does not undergo hydrolysis.

- **Potassium Cyanide (KCN)**:
- KCN is formed from the strong base (KOH) and the weak acid (HCN).
- Hydrolysis: KCN + H2O → KOH + HCN
- This salt will undergo hydrolysis because it contains a weak acid.

- **Potassium Formate (HCOOK)**:
- HCOOK is formed from the strong base (KOH) and the weak acid (HCOOH).
- Hydrolysis: HCOOK + H2O → KOH + HCOOH
- This salt will also undergo hydrolysis due to the weak acid.

- **Potassium Acetate (CH3COOK)**:
- CH3COOK is formed from the strong base (KOH) and the weak acid (CH3COOH).
- Hydrolysis: CH3COOK + H2O → KOH + CH3COOH
- This salt will also undergo hydrolysis because it contains a weak acid.

4. **Conclusion**: Among the four salts analyzed, only potassium nitrate (KNO3) does not undergo hydrolysis because it is a salt derived from a strong acid and a strong base.

### Final Answer:
**Potassium nitrate (KNO3) will not be hydrolyzed.**