A is a lighter phenol and B is an aromatic carboxylic acid . Separation of a mixture of A and B can be carried out easily by using a solution of

Options

A. sodium hydroxide
B. sodium sulphate
C. calcium chloride
D. sodium bicarbonate

Explanation

To separate a mixture of a lighter phenol (A) and an aromatic carboxylic acid (B), we can utilize sodium bicarbonate (NaHCO3) as a separating agent. Here’s a step-by-step solution:

### Step-by-Step Solution:

1. **Understanding the Compounds**:
- A is a lighter phenol, which is a weak acid.
- B is an aromatic carboxylic acid, which is a stronger acid compared to phenol.

2. **Choosing the Right Reagent**:
- Sodium bicarbonate (NaHCO3) is a weak base that can react with stronger acids to form a salt and carbon dioxide (CO2).

3. **Reaction with Sodium Bicarbonate**:
- When the mixture of phenol and carboxylic acid is treated with sodium bicarbonate, only the carboxylic acid (B) will react. The reaction can be represented as:
\[ \text{RCOOH} + \text{NaHCO}_3 \rightarrow \text{RCOONa} + \text{CO}_2 + \text{H}_2\text{O} \]
- Here, RCOOH represents the carboxylic acid, which forms a sodium salt (RCOONa), while CO2 gas is evolved.

4. **Observation of the Reaction**:
- The evolution of CO2 gas can be observed, which will turn lime water milky if bubbled through it, indicating the presence of a carboxylic acid.

5. **Separation of the Components**:
- After the reaction, the mixture will contain the sodium salt of the carboxylic acid (which is soluble in water) and unreacted phenol (which remains in the organic phase).
- The aqueous layer can be separated from the organic layer, effectively separating the phenol (A) from the carboxylic acid (B).

6. **Conclusion**:
- Thus, by using sodium bicarbonate, we can easily separate the lighter phenol from the aromatic carboxylic acid.

### Final Answer:
The separation of a mixture of a lighter phenol (A) and an aromatic carboxylic acid (B) can be carried out easily by using a solution of sodium bicarbonate (NaHCO3).

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