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Consider the following reaction sequence: X (PhCOOH, benzoic acid) + NH3/H2SO4 -> P --[HNO2 then H2O/heat]--> Q X + NH3/heat -> R --[Br2/NaOH]--> S --[Se/heat]--> T Based on the above sequence, choose the correct option(s).

1. (Q) will give positive Br2, H2O test
2. (R) on reaction with NaNO2, HCl produces (X)
3. Major product (P) & (S) are identical
4. Reaction sequence involves schmidt & Hoffmann bromamide degradation reaction

Correct answer: (R) on reaction with NaNO2, HCl produces (X)

Solution

Benzamide (R) reacts with NaNO2/HCl to form a diazonium-type intermediate that hydrolyses on heating to regenerate benzoic acid (X), making option B correct. Option A is wrong since Q = benzoic acid does not give Br2/H2O test.

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