In the reaction
`"Phenol" overset(NaOH) to (A) underset(140)overset(CO_(2) + HCl) to (B) ` here B is

Options

A. Benzoic acid
B. Salicylic acid
C. Benzaldehyde
D. Salicyladehyde

Answer

To solve the question, we will follow the steps outlined in the video transcript regarding the reactions of phenol.

### Step 1: Reaction of Phenol with NaOH
- **Phenol (C6H5OH)** reacts with **sodium hydroxide (NaOH)**.
- This reaction leads to the formation of the sodium salt of phenol, which can be represented as **C6H5O^- Na^+** (sodium phenoxide).

**Product A**: Sodium phenoxide (C6H5O^- Na^+)

### Step 2: Reaction of Sodium Phenoxide with CO2 and HCl
- The sodium phenoxide then undergoes a reaction with **carbon dioxide (CO2)** in the presence of **hydrochloric acid (HCl)**.
- In this reaction, the sodium ion (Na^+) is replaced by a carboxylic acid group (COOH), converting the sodium phenoxide back to a phenolic compound with an additional carboxylic acid group.
- The product formed is **salicylic acid (C6H4(OH)COOH)**, which has both a hydroxyl group (OH) and a carboxylic acid group (COOH) on the aromatic ring.

**Product B**: Salicylic acid (C6H4(OH)COOH)

### Final Answer
Thus, the product B in the reaction is **salicylic acid**.

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