Which of the following is not a salt?

Options

A. Sodium chloride
B. Slaked lime
C. Lead sulphide
D. Zinc nitrate

Explanation

To determine which of the following options is not a salt, we will analyze each option provided.

### Step-by-Step Solution:

1. **Identify the first option: Sodium Chloride (NaCl)**
- Sodium Chloride is formed from hydrochloric acid (HCl) and sodium hydroxide (NaOH).
- Both HCl and NaOH are strong acid and strong base, respectively.
- Therefore, NaCl is a neutral salt.

2. **Identify the second option: Slaked Lime (Ca(OH)₂)**
- Slaked lime is chemically known as calcium hydroxide.
- It is a base and does not result from the neutralization of an acid and a base.
- Therefore, slaked lime is not a salt.

3. **Identify the third option: Lead Sulphide (PbS)**
- Lead Sulphide is formed from lead (II) ions and sulfide ions.
- Lead (II) ions come from weak acid (hydrogen sulfide, H₂S) and sulfide ions are derived from a weak base.
- Therefore, PbS is a neutral salt.

4. **Identify the fourth option: Zinc Nitrate (Zn(NO₃)₂)**
- Zinc Nitrate is formed from nitric acid (HNO₃) and zinc hydroxide (Zn(OH)₂).
- Nitric acid is a strong acid, while zinc hydroxide is a weak base.
- Thus, zinc nitrate is classified as an acidic salt.

### Conclusion:
After analyzing all the options, the only option that is not a salt is **Slaked Lime (Ca(OH)₂)**.

### Final Answer:
**The option that is not a salt is Slaked Lime (Ca(OH)₂).**

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