Target Exam

CUET

Subject

Chemistry

Chapter

Organic: Aldehydes, Ketones and Carboxylic Acids

Question:

What is the product of nitration of Benzoic acid?

Options:

o-Nitrobenzoic acid

m-Nitrobenzoic acid

o-Nitrobenzoic acid and p-Nitrobenzoic acid

p-Nitrobenzoic acid

Correct Answer:

m-Nitrobenzoic acid

Explanation:

The correct answer is Option (2) → m-Nitrobenzoic acid

Benzoic acid contains the –COOH group attached to the benzene ring.

The –COOH group is:

Electron withdrawing

Deactivating

Meta-directing

Reason for Meta Direction

The –COOH group withdraws electrons through:

Inductive effect (–I)

Resonance effect (–M)

This reduces electron density at:

Ortho position

Para position

But comparatively leaves meta position less deactivated.

Electrophilic substitution like nitration occurs where electron density is relatively higher.

Thus substitution occurs at meta position.

Reaction:

Benzoic acid + Nitrating mixture (HNO3 / H2SO4)

Gives predominantly:

m-Nitrobenzoic acid

Why not ortho or para?

Formation of ortho/para sigma-complex places positive charge near the electron-withdrawing –COOH group, making it highly unstable.

Meta substitution avoids this destabilization.