Question

Assertion (A) : The presence of \( -OH \) group in phenols directs the incoming group to ortho and para positions.
Reason (R) : \( -OH \) group in phenols activates the aromatic ring towards electrophilic substitution reaction.

Hint:

Groups that activate the benzene ring by \( +M \) or \( +I \) effects (like \( -OH, -NH_2, -CH_3 \)) are typically ortho-para directors.

Answer 1

Step 1: Understanding the Concept:
Phenol molecules undergo electrophilic aromatic substitution very easily due to the electron-releasing nature of the hydroxyl group.
Step 2: Detailed Explanation:
The \( -OH \) group has lone pairs on oxygen which are in conjugation with the benzene ring.
By the resonance effect (\( +M \) effect), it increases the electron density on the ring, especially at the ortho and para positions.
This high electron density makes these positions more reactive towards electrophiles (Activation).
Since the density is highest at ortho and para, the electrophile attacks there, making the group o,p-directing.
Thus, both statements are true and R explains why substitution occurs at o/p positions.
Step 3: Final Answer:
Code (A) is correct.