Which of the following is an acidic salt/

Options

A. `Na_(2)HPO_(3)`
B. `NH_(4)NO_(3)`
C. `NaH_(2)PO_(2)`
D. `NaHCO_(3)`

Answer

To determine which of the given options is an acidic salt, we need to analyze each option based on the nature of the acid and base involved in its formation. An acidic salt is formed when a strong acid reacts with a weak base.

### Step-by-Step Solution:

1. **Understand the Concept of Acidic Salts**:
- Acidic salts are formed from the reaction of a strong acid with a weak base. The resulting salt will have acidic properties.

2. **Analyze Each Option**:
- **Option A: Na2HPO3**
- This salt is formed from the reaction of sodium hydroxide (NaOH) and carbonic acid (H3CO3).
- NaOH is a strong base, and H3CO3 is a weak acid.
- Therefore, this salt is basic in nature. **(Not an acidic salt)**

- **Option B: NH4NO3**
- This salt is formed from the reaction of ammonium hydroxide (NH4OH) and nitric acid (HNO3).
- NH4OH is a weak base, and HNO3 is a strong acid.
- Therefore, this salt is acidic in nature. **(This is an acidic salt)**

- **Option C: NaH2PO2**
- This salt is formed from the reaction of sodium hydroxide (NaOH) and phosphorous acid (H3PO2).
- NaOH is a strong base, and H3PO2 is a weak acid.
- Therefore, this salt is basic in nature. **(Not an acidic salt)**

- **Option D: NaHCO3**
- This salt is formed from the reaction of sodium hydroxide (NaOH) and carbonic acid (H2CO3).
- NaOH is a strong base, and H2CO3 is a weak acid.
- Therefore, this salt is basic in nature. **(Not an acidic salt)**

3. **Conclusion**:
- Based on the analysis, the only option that represents an acidic salt is **Option B: NH4NO3**.

### Final Answer:
**Option B is the correct answer, as it is the only acidic salt among the given options.**