Question

What is the product of the reaction between Phenol and concentrated \(HNO_3\)?

• A. Nitrobenzene
• B. Picric Acid (2,4,6-trinitrophenol)
• C. Aniline
• D. Benzaldehyde

Hint:

Phenol is highly activated due to the \(-OH\) group, so strong nitration with concentrated \(HNO_3\) produces picric acid (2,4,6-trinitrophenol).

Answer 1

The Correct Option is B

Concept: Phenol undergoes electrophilic substitution reactions easily because the hydroxyl group (\(-OH\)) strongly activates the benzene ring and directs incoming electrophiles to the ortho and para positions.

Step 1: Reaction with concentrated nitric acid. When phenol reacts with concentrated nitric acid, strong nitration occurs due to the highly activated aromatic ring.

Step 2: Formation of trinitro compound. Three nitro groups (\(-NO_2\)) are introduced at the 2, 4, and 6 positions of the benzene ring. The product formed is: \[ \text{2,4,6-trinitrophenol} \] This compound is commonly known as Picric Acid.

Step 3: Conclusion. Hence, the reaction of phenol with concentrated \(HNO_3\) produces Picric Acid (2,4,6-trinitrophenol).