Examine the assertion

Assertion A: Aniline on nitration yields ortho, meta and para nitro derivatives of aniline.

• Aniline is $\ce{C6H5NH2}$.
• Normally, the $\ce{-NH2}$ group is an activating, ortho-para directing group.
• However, nitration is carried out using a strongly acidic nitrating mixture (generally conc. $\ce{HNO3}$ and conc. $\ce{H2SO4}$).
• In this acidic medium, aniline gets protonated: $\ce{C6H5NH2 + H+ -> C6H5NH3+}$
• The anilinium ion $\ce{-NH3+}$ is deactivating and meta directing.
• Therefore, during nitration, a mixture of products can form: ortho and para products from unprotonated aniline, and meta product due to protonated aniline.

Hence, Assertion A is true.

Examine the reason

Reason R: Nitrating mixture is a strong acidic mixture.

• This is correct.
• The nitrating mixture contains concentrated acids and is strongly acidic.
• Because of this acidity, aniline gets protonated to the anilinium ion.

Hence, Reason R is true.

Check whether R explains A

• The strong acidic nature of the nitrating mixture causes protonation of aniline.
• This changes the directing effect and leads to formation of the meta product along with ortho and para products.
• Thus, the reason directly explains why nitration of aniline gives all three isomers.

Therefore, R is the correct explanation of A.

Correct option

$\boxed{\text{A: Both A and R are true and R is the correct explanation of A}}$

Comparison with stored answer

• Derived answer: A
• Stored correct answer: A

They match.