Question

Phenol is treated with conc. $ H_2SO_4 $, and then with conc. $ HNO_3 $. The compound A and B are formed.

• A. A is phenol, B is nitrobenzene
• B. A is phenol, B is benzene
• C. A is phenol, B is phenol derivative
• D. A is phenol, B is benzene derivative

Hint:

In organic reactions, when phenol undergoes nitration with \( HNO_3 \) after treatment with \( H_2SO_4 \), nitrobenzene is typically formed.

Answer 1

The Correct Option is A

In the given reaction, phenol (C6H5OH) is first treated with concentrated sulfuric acid (\( H_2SO_4 \)) and then with concentrated nitric acid (\( HNO_3 \)). 
- The reaction of phenol with \( H_2SO_4 \) leads to the formation of phenolsulfonic acid, which introduces a sulfonic acid group (\( SO_3H \)) to the phenol ring. 
- After that, when phenolsulfonic acid reacts with concentrated nitric acid (\( HNO_3 \)), it undergoes nitration, which introduces a nitro group (\( NO_2 \)) at the meta position of the ring, leading to the formation of nitrobenzene. 
Thus, the compound A is phenol, and the compound B is nitrobenzene. The correct answer is \( A \).