JEE Main · 2026 · 23 Jan 2026 · Shift 2 · Aldehydes Ketones and Carboxylic Acids

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Iodoform test can differentiate between
A. Methanol and Ethanol
B. and
C. Cyclohexene and cyclohexanone
D. Diethyl ether and Pentan-3-one
E. Anisole and acetone

Choose the correct answer from the options given below:
  1. (A)A & E only✓ Correct
  2. (B)A & D only
  3. (C)A, B & E only
  4. (D)B, C & E only

Answer: (A)

Solution

The iodoform test is given only by ethanol, by methyl carbinols and by methyl ketones . Methanol gives no precipitate while ethanol does, so that pair is distinguished, and anisole gives none while acetone does, so that pair is distinguished too. In contrast and both fail, cyclohexene and cyclohexanone both fail (cyclohexanone has no group), and diethyl ether and pentan-3-one both fail, so none of those pairs can be told apart. The test separates only the methanol/ethanol and anisole/acetone pairs.

JEE Main · 2026 · 23 Jan 2026 · Shift 2 · Single correct option

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