$\mathrm{A} \xrightarrow[\text { (ii) } \mathrm{H}_{3} \mathrm{O}^{+}]{\text {(i) } \mathrm{NaOH}} \mathrm{B} \xrightarrow[\text { (ii) } \mathrm{H}_{2} \mathrm{SO}_{4}, \Delta]{\text { (i) } \mathrm{EtOH}} \mathrm{C}$ 'A' shows positive Lassaign's test for N and its molar mass is 121. ' B ' gives effervescence with aq. $\mathrm{NaHCO}_{3}$. 'C' gives fruity smell. Identify $\mathrm{A}, \mathrm{B}$ and C from the following.

JEE Main · 2025 · 08 Apr 2025 · Shift 2 · Practical and Analytical Chemistry

A (i) NaOH (ii) H_{3} O^{+} B (i) EtOH (ii) H_{2} SO_{4}, Δ C

'A' shows positive Lassaign's test for N and its molar mass is 121.
' B ' gives effervescence with aq.

NaHCO_{3}

.
'C' gives fruity smell.
Identify

A, B

and C from the following.

(A)(see structures)
✓ Correct
(B)(see structures)
A
B
C
(C)(see structures)
(D)(see structures)
A
B
C

Answer: (A)

Solution

A positive Lassaigne test shows nitrogen in the molecule, and a molar mass of 121 matches benzamide,

C_{6} H_{5} CON H_{2}

. Alkaline hydrolysis followed by acidification turns this amide into benzoic acid, which liberates carbon dioxide with aqueous sodium bicarbonate, so the intermediate is benzoic acid. Heating benzoic acid with ethanol and concentrated sulphuric acid esterifies it to ethyl benzoate, an ester with a characteristic fruity odour. Thus the starting amide is benzamide, the acid is benzoic acid and the ester is ethyl benzoate.

JEE Main · 2025 · 08 Apr 2025 · Shift 2 · Single correct option

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JEE Main · 2025 · 08 Apr 2025 · Shift 2 · Practical and Analytical Chemistry

Solution

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