Which of the following is an acidic salt that can form an alkaline solution ?

Options

A. `NaHSO_(4)`
B. `NaHCO_(3)`
C. `Na_(2)HPO_(3)`
D. `Na_(2)HPO_(4)`

Answer

To determine which of the following is an acidic salt that can form an alkaline solution, we need to understand the characteristics of acidic salts and how they behave in solution.

### Step-by-Step Solution:

1. **Understand Acidic Salts**:
- An acidic salt is formed from a weak acid and a strong base. It contains replaceable hydrogen ions (H⁺) that can affect the pH of the solution.
- Example: Sodium bicarbonate (NaHCO₃) is derived from carbonic acid (H₂CO₃), which is a weak acid, and sodium hydroxide (NaOH), which is a strong base.

2. **Identify the Components**:
- In the case of NaHCO₃:
- Sodium (Na⁺) comes from the strong base (NaOH).
- Bicarbonate (HCO₃⁻) comes from the weak acid (H₂CO₃).

3. **Dissociation in Water**:
- When NaHCO₃ is dissolved in water, it dissociates into Na⁺ and HCO₃⁻ ions.
- The bicarbonate ion (HCO₃⁻) can undergo hydrolysis:
\[ \text{HCO}_3^- + \text{H}_2\text{O} \rightleftharpoons \text{H}_2\text{CO}_3 + \text{OH}^- \]
- This reaction produces hydroxide ions (OH⁻), which increases the pH of the solution, making it alkaline.

4. **Conclusion**:
- Since NaHCO₃ is formed from a strong base (NaOH) and a weak acid (H₂CO₃), it is an acidic salt that can form an alkaline solution upon hydrolysis.

### Final Answer:
The acidic salt that can form an alkaline solution is **NaHCO₃** (sodium bicarbonate).

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