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

Hint: 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

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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.