Step 1: Understanding reaction type.
The reaction involves nitration of aniline using a mixture of concentrated nitric acid and sulfuric acid. This is an electrophilic aromatic substitution reaction where the electrophile is the nitronium ion (\(NO_2^+\)). Step 2: Effect of \(-NH_2\) group.
The \(-NH_2\) group is a strong activating and ortho/para directing group due to resonance donation of electron density into the benzene ring. Hence substitution occurs mainly at ortho and para positions. Step 3: Formation of products.
At low temperature (288 K), controlled nitration occurs giving a mixture of:
- ortho-nitroaniline (P)
- para-nitroaniline (Q, major due to less steric hindrance) Step 4: Reason for major product.
Para position is less sterically hindered compared to ortho position, so electrophilic attack is favored there, making p-nitroaniline the major product. Step 5: Meta product absence.
Meta product is not formed significantly because \(-NH_2\) group strongly directs substitution to ortho/para positions via resonance stabilization of intermediate carbocation. Step 6: Final conclusion.
Thus, the reaction produces a mixture of ortho and para nitroaniline derivatives, with para being the major product. Final Answer:
\[
\boxed{P = o\text{-nitroaniline},\ Q = p\text{-nitroaniline}}
\]
