Exams › JEE Advanced › Chemistry

Match each compound in List-I with the correct chemical test in List-II: List-I: P: CH3CH2OH (ethanol) Q: C6H5CHO (benzaldehyde) R: C6H5OH (phenol) S: CH3COOH (acetic acid) List-II: 1: Tollens test (silver mirror test) 2: Fehling solution test 3: Iodoform test 4: Bromine water test 5: NaHCO3 test

1. P-3, Q-1, R-4, S-5
2. P-1, Q-2, R-3, S-4
3. P-2, Q-3, R-5, S-1
4. P-4, Q-5, R-1, S-2

Correct answer: P-3, Q-1, R-4, S-5

Solution

P (CH3CH2OH): Iodoform test - ethanol has CH3CH2OH structure; on oxidation gives CH3CHO which gives iodoform. More directly, ethanol (methyl carbinol) gives iodoform test because it contains the -CHOH-CH3 unit. P -> 3. Q (C6H5CHO): Tollens test - benzaldehyde is an aldehyde (aromatic); it gives silver mirror with Tollens reagent but NOT Fehling (aromatic aldehydes do not reduce Fehling). Q -> 1. R (C6H5OH): Bromine water test - phenol reacts with Br2 water to give 2,4,6-tribromophenol (white precipitate), decolorizing Br2. R -> 4. S (CH3COOH): NaHCO3 test - carboxylic acids react with NaHCO3 to give CO2 effervescence. S -> 5. Answer: P-3, Q-1, R-4, S-5.

Related JEE Advanced Chemistry questions

• Identify the correct combination for preparing benzoic acid using the given starting materials, reaction conditions, and reaction types.
• Consider the molecule Ph-CO-CH2-CH2-CO2Me (methyl 4-oxo-4-phenylbutanoate), which contains both a ketone group and a methyl ester group. Which of the following reagents will selectively reduce only the ketone to give Ph-CH(OH)-CH2-CH2-CO2Me, leaving the ester intact?
• Which of the following statements is INCORRECT regarding NaBH4?
• From the compounds listed below, how many will give a POSITIVE iodoform test but a NEGATIVE Tollens' test? (a) Ethanal (CH3CHO) (b) Propan-2-one (CH3COCH3) (c) Butan-2-ol (CH3CH(OH)CH2CH3) (d) 4-acetylbenzaldehyde (OHC-C6H4-COCH3) (e) Cyclopropyl methyl ketone (cyclopropane ring bearing a -COCH3 group) (f) A cyclopentanone derivative bearing both an aldehyde (-CHO) and an acetyl (-COCH3) substituent (g) Ethanol (CH3CH2OH) (h) Acetic acid (CH3COOH) (i) Acetophenone (C6H5COCH3)
• Among the following carboxylic acids, which one undergoes decarboxylation most easily upon heating?
• A vinyl ether (cyclohexyl enol ether where one cyclohexyl group is attached to the oxygen and a cyclohexenyl group forms the vinyl part) undergoes acid-catalyzed hydrolysis (H+ / H2O) to give two products P and Q. On treatment with concentrated H2SO4 and heat, P and Q both give the same alkene R of molecular formula C6H10. Identify Q.

⚔️ Practice JEE Advanced Chemistry free + battle 1v1 →