The compuond that does no liberate `CO_(2)` on treatment with aqueous sodium bicarbonate solution is `:`

Options

A. Benzoic acid
B. Benzensulphonic acid
C. Salicylic acid
D. Carbolic acid (Phenol)

Answer

To determine which compound does not liberate CO₂ when treated with aqueous sodium bicarbonate (NaHCO₃), we need to analyze the acidic properties of the given compounds: benzoic acid, benzene sulfonic acid, salicylic acid, and carbolic acid (phenol).

### Step-by-Step Solution:

1. **Identify the Compounds**: The compounds in question are:
- Benzoic Acid (C₇H₆O₂)
- Benzene Sulfonic Acid (C₆H₅SO₃H)
- Salicylic Acid (C₇H₆O₃)
- Carbolic Acid (Phenol, C₆H₆O)

2. **Understand the Reaction with Sodium Bicarbonate**: Sodium bicarbonate reacts with acids to produce carbon dioxide (CO₂) gas. The reaction generally occurs with acids that have a pKa value lower than that of carbonic acid (H₂CO₃), which has a pKa of approximately 6.63.

3. **Determine the pKa Values**:
- **Benzoic Acid**: pKa ≈ 4.2 (stronger acid, will liberate CO₂)
- **Benzene Sulfonic Acid**: pKa ≈ -2.5 (stronger acid, will liberate CO₂)
- **Salicylic Acid**: pKa ≈ 2.7 (stronger acid, will liberate CO₂)
- **Carbolic Acid (Phenol)**: pKa ≈ 9.98 (weaker acid, will not liberate CO₂)

4. **Analyze the Results**:
- Benzoic acid, benzene sulfonic acid, and salicylic acid all have lower pKa values than carbonic acid, indicating that they are stronger acids and will liberate CO₂ when reacted with sodium bicarbonate.
- Carbolic acid (phenol), with a pKa of 9.98, is a much weaker acid and will not liberate CO₂ when treated with sodium bicarbonate.

5. **Conclusion**: The compound that does not liberate CO₂ on treatment with aqueous sodium bicarbonate is **Carbolic Acid (Phenol)**.

### Final Answer:
The compound that does not liberate CO₂ on treatment with aqueous sodium bicarbonate solution is **Carbolic Acid (Phenol)**.