Question

What is the functional group of alcohol and phenol?
A) $- OH$ Phenol and alcohol
B) Phenol and $- OH$ alcohol
C) $- OH$ Alcohol and $- COOH$ Phenol
D) None of the above

Answer 1

The general formula of alcohol is ${C_n}{H_{2n + 1}}OH$. Alcohol and phenol is the two organic compounds containing the hydroxyl group i.e. $- OH$ in common.
We have to know that alcohol is an organic compound which has at least one hydroxyl group which is attached to the saturated carbon atom chain.

Complete step by step answer:
We have to remember that the nomenclature for writing the name of alcohol is Suffix “ol” is used when hydroxyl group is present as a higher priority in any compound whereas Prefix “hydroxy” is used when other groups are present as higher priority than alcohol.
Examples of alcohol:
${C_2}{H_5}OH$- Ethanol
Phenol is an aromatic organic compound that contains hydroxyl group which is attached to a benzene ring therefore the functional group is $-{C_6}{H_5}OH$or
Image created in chemdraw by SME.
Phenol is a weak acid that has pH of $8 - 12$ , there is resonance stabilization in phenol due to which it is more acidic than aliphatic alcohols.
Option A) this is an incorrect option as $- OH$ is a functional group of alcohol and is the functional group of phenol.
Option B) This is a correct option as the two represent phenol and alcohol in the correct way.
Option C) this is an incorrect option as $- OH$ is a functional group of alcohol but $- COOH$ is a functional group of carboxylic acid and not phenol.
Option D) this is an incorrect option as we get option B as the correct option.

Hence, the correct option is, ‘Option B’.

Note: We need to know that an alcohol is an aliphatic organic compound whereas Phenol is an aromatic organic compound. Phenols have generally higher acidity than alcohols.