give a chemical test to distinguish between the following pairs of compounds I. Phenol and cyclohexanol. II. Propan-2-ol and benzylalcohol

You can distinguish between Phenol and Alcohol using Aq. Br2 water. It always gives white ppt with Phenols whereas it does not form any ppt with alcohols.

Propan-2-ol and benzyl alcohol can be distinguished byiodofrom test.
Iodoform test is given by compounds containing eitherCH3– CO– or CH3– CHOH –group linked to carbon.

[The iodoform test or reaction is a chemical reaction where yellow iodoform (CHI3) is produced by the multiple halogenation of a methyl ketone (a molecule containing the R-CO-CH3group) or alcohol with 2-ol structure (a molecule containing the R-CHOH-CH3group) in the presence of a base.]
Propan-2-ol contains CH3– CHOH – group linked to carbon and hence will give yellow precipitate of iodofrom [ CHI3].
Benzyl alcohol does not contain either of the groups and hence will not and hence will not give yellow precipitate of iodofrom [ CHI3].

Dear Student,
Please find below the solution to your problem.

You can distinguish between Phenol and Alcohol using Aq. Br2 water. It always gives white ppt with Phenols whereas it does not form any ppt with alcohols. Propan-2-ol and benzyl alcohol can be distinguished byiodofrom test. Iodoform test is given by compounds containing eitherCH3– CO– or CH3– CHOH –group linked to carbon. [The iodoform test or reaction is a chemical reaction where yellow iodoform (CHI3) is produced by the multiple halogenation of a methyl ketone (a molecule containing the R-CO-CH3group) or alcohol with 2-ol structure (a molecule containing the R-CHOH-CH3group) in the presence of a base.] Propan-2-ol contains CH3– CHOH – group linked to carbon and hence will give yellow precipitate of iodofrom [ CHI3]. Benzyl alcohol does not contain either of the groups and hence will not and hence will not give yellow precipitate of iodofrom [ CHI3].

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