JEE Chemistry 2026 Question with Solution

Given: Four aromatic isomeric compounds $P, Q, R, S$ are provided. $P$ contains $-\mathrm{OH}$, $Q$ contains $-\mathrm{CHO}$, and $R, S$ are ketones.

Find: Which among statements A to E are correct.

Step 1: Test with $2,4$-DNP

$2,4$-DNP gives a precipitate with aldehydes and ketones.

• $Q$: aldehyde ✓
• $R$: ketone ✓
• $S$: ketone ✓
• $P$: alcohol ✗

Step 2: Baeyer’s test

Baeyer’s test is given by compounds containing $\mathrm{C=C}$ or $\mathrm{C\equiv C}$.

• $P$: phenolic compound, no alkene ✗
• $Q$: aldehyde, no alkene ✗

Step 3: Sooty flame test

Aromatic compounds generally burn with a sooty flame due to high carbon content.

Step 4: Iodoform test

Iodoform test is given by methyl ketones $(-\mathrm{COCH_3})$ and ethanol.

Only compound $S$ is a methyl ketone, not $R$.

Step 5: Tollens’ test

Tollens’ reagent gives a silver mirror with aldehydes.

Others are ketones or alcohols.

Therefore, the correct statements are A, C and E only. The correct option is D.

Given: The compounds differ by functional group placement on an aromatic framework.

Find: Which statements survive functional group tests.

Use each named test separately:

1. $2,4$-DNP test identifies carbonyl compounds of aldehyde and ketone type. So $Q, R, S$ respond, while $P$ does not.
2. Baeyer’s test is for unsaturation such as $\mathrm{C=C}$ or $\mathrm{C\equiv C}$, not for a phenolic $-\mathrm{OH}$ or an aldehyde group alone here. So statement B is rejected.
3. Sooty flame is expected for aromatic compounds, so the listed aromatic compounds $Q$ and $R$ satisfy statement C.
4. Iodoform test requires a methyl ketone. The solution identifies only $S$ as methyl ketone, so the pair $R$ and $S$ is incorrect. Hence D is false.
5. Tollens’ reagent is positive for aldehydes, so only $Q$ gives silver deposition.

Thus only statements A, C, E are correct, so the correct option is D.