Question

Consider the following reactions:
 
 Y and Z respectively are:

• A. Picric acid (2,4,6 – Trinitrophenol), 2,4,6 – Tribromophenol
• B. o – Nitrophenol, p – Bromophenol
• C. p – Nitrophenol, o – Bromophenol
• D. 2,4 – Dinitrophenol, 2,4 – Dibromophenol

Hint:

Phenol is highly reactive towards electrophilic substitution due to the electron-donating effect of the hydroxyl group, making it susceptible to nitration and bromination.

Answer 1

The Correct Option is A

To determine the correct identity of Y and Z, let's analyze the given reactions which involve phenol. The suggested reactions could be:

• Nitration of phenol: When phenol undergoes nitration in the presence of concentrated nitric acid and sulfuric acid, it results in the formation of Picric acid (2,4,6 - Trinitrophenol).
• Halogenation of phenol: When phenol reacts with bromine water, it leads to the formation of 2,4,6 - Tribromophenol.

For the nitration reaction: Phenol + HNO₃ (Concentrated) → 2,4,6 - Trinitrophenol (Picric acid). For the halogenation reaction: Phenol + Br₂ (aq) → 2,4,6 - Tribromophenol.

Therefore, Y is Picric acid (2,4,6 - Trinitrophenol) and Z is 2,4,6 - Tribromophenol.

Compound	Number
Y	Picric acid (2,4,6 - Trinitrophenol)
Z	2,4,6 - Tribromophenol

Answer 2

Step 1: Hydrolysis of Chlorobenzene
Chlorobenzene undergoes hydrolysis under aqueous conditions at 283 K to form phenol: \[ \text{C}_6\text{H}_5\text{Cl} + \text{H}_2\text{O} \rightarrow \text{C}_6\text{H}_5\text{OH} (Y) \] Step 2: Nitration of Phenol
Phenol undergoes nitration with concentrated nitric acid, resulting in the formation of picric acid (2,4,6-trinitrophenol) due to the activating effect of the hydroxyl group: \[ \text{C}_6\text{H}_5\text{OH} + 3\text{HNO}_3 \rightarrow 2,4,6-\text{Trinitrophenol} (Z) \] Step 3: Bromination of Phenol
When phenol is treated with bromine water, it undergoes electrophilic substitution at the ortho and para positions, leading to 2,4,6-Tribromophenol: \[ \text{C}_6\text{H}_5\text{OH} + 3\text{Br}_2 \rightarrow 2,4,6-\text{Tribromophenol} \] Final Answer:
Thus, the correct answer is Picric acid (2,4,6 – Trinitrophenol) and 2,4,6 – Tribromophenol.