Chapter 11. Alcohols, Phenols and Ethers Chapter 11 Alcohols, Phenols and Ethers, Class 12 | Page 9

Physical Properties of Phenols
1 . These are colourless liquids or crystalline solids but become coloured due to slow oxidation with air .
2 . Phenol is also called carbolic acid .
3 . Because of the presence of polar -OH bond , phenols form intermolecular H-bonding with other phenol molecules and with water .
Chemical Reactions of Alcohols and Phenols
( i ) Reactions involving cleavage of O – H Bond ( a ) Acidity of alcohols and phenols
Alcohols are weaker acids than water due to + 1 group present in alcohols , which decreases the polarity of -O-H bond .
Acid strength of alcohol
Electron releasing group increases electron density on oxygen to decrease the polarity of – OH bond .