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Which of the following reagents can be used to distinguish between methanol and ethanol?

1. Concentrated HCl and ZnCl2
2. CH3COOH in the presence of H+
3. NaOH and I2
4. None of the above

Correct answer: NaOH and I2

Solution

Ethanol (CH3CH2OH) contains the CH3CH(OH)- group and gives a yellow iodoform precipitate (CHI3) with NaOH/I2, whereas methanol (CH3OH) does not, making this reagent pair a valid distinguishing test.

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