Which one of the following salts gives aqueous solution which is weakly basic ?

Options

A. `NaHCO_(3)`
B. `NaHSO_(4)`
C. `NaCl`
D. `NH_(4)HCO_(3)`

Explanation

To determine which salt gives a weakly basic aqueous solution, we need to analyze the nature of the salts provided. A solution is considered weakly basic if it is derived from a strong base and a weak acid.

### Step-by-Step Solution:

1. **Identify the Salts**: Let's consider the salts mentioned in the transcript. The salts we can analyze are:
- NaHCO₃ (Sodium bicarbonate)
- NaHSO₄ (Sodium bisulfate)
- Na₄ (not clearly mentioned, but likely refers to a salt like Na₂CO₃ or NaOH)
- H₂CO₃ (Carbonic acid, but not a salt)

2. **Determine the Nature of Each Salt**:
- **NaHCO₃**: This salt is derived from sodium hydroxide (a strong base) and carbonic acid (a weak acid). When dissolved in water, it can produce bicarbonate ions (HCO₃⁻), which can accept protons, making the solution weakly basic.
- **NaHSO₄**: This salt is derived from sodium hydroxide (strong base) and sulfuric acid (strong acid). The solution will be acidic due to the presence of HSO₄⁻, which can release protons.
- **Na₂CO₃** (assuming this is what Na₄ refers to): This salt is derived from sodium hydroxide (strong base) and carbonic acid (weak acid). It produces carbonate ions (CO₃²⁻), which can also make the solution basic, but stronger than NaHCO₃.
- **H₂CO₃**: This is not a salt but a weak acid itself.

3. **Conclusion**: Among the salts analyzed, **NaHCO₃ (Sodium bicarbonate)** is the one that gives a weakly basic solution when dissolved in water. It is derived from a strong base (NaOH) and a weak acid (H₂CO₃), which is the condition for a weakly basic solution.

### Final Answer:
**NaHCO₃ (Sodium bicarbonate)** gives an aqueous solution that is weakly basic.

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