Alcohols, Phenols, and Ethers — Practice

Question 1

Distinguish between ethanol and phenol using a chemical test.

Accepted Answer

Add neutral FeCl3: phenol gives a violet colour, while ethanol gives no colouration.

Question 2

What is the product when phenol reacts with excess bromine water?

Accepted Answer

2,4,6-tribromophenol, formed as a white precipitate -- a test for phenol.

Question 3

Arrange in decreasing order of acidity: water, ethanol, phenol, p-nitrophenol.

Accepted Answer

p-nitrophenol > phenol > water > ethanol. The electron-withdrawing nitro group increases acidity; phenoxide is resonance-stabilised; ethoxide is not.

Question 4

Write the product when anisole (CH3OC6H5) reacts with HI.

Accepted Answer

Phenol (C6H5OH) and methyl iodide (CH3I); the smaller methyl group forms the alkyl iodide.

Question 5

Name and complete: C6H5ONa + CO2 followed by H+ gives what?

Accepted Answer

Kolbe's reaction, giving salicylic acid (2-hydroxybenzoic acid), a precursor of aspirin.

Practice — Alcohols, Phenols, and Ethers