Explain the following terms with suitable examples :
(a) Cationic detergents
(b) Anionic detergents
Answers
Answer:
(i) Cationic detergents: Cationic detergents are quarternary ammonium salts of amines with acetates, chlorides or bromides as anions. ... For example cetyltrimethylammonium bromide .
(ii) Anionic detergents: Anionic detergents are sodium salts of sulphonated long chain alcohols or hydrocarbon.
Answer:
(i) Cationic detergents: Cationic detergents are quarternary ammonium salts of amines with acetates, chlorides or bromides as anions. Cationic part possess a long hydrocarbon chain and a positive charge on nitrogen atom. Hence, these are called cationic detergents. For example cetyltrimethylammonium bromide .
(ii) Anionic detergents: Anionic detergents are sodium salts of sulphonated long chain alcohols or hydrocarbon. The long chain alcohols are treated with concentrated sulphuric acid to form alkyl hydrogen sulphate of high molecular mass and finally alkyl sulphate are neutralised with alkali to form salts.
It is called anionic detergent because large part of the molecule is anion. The single anionic detergent is in largest use today in household detergents is alkyl-benze-sulphonate.
They are effective in acidic solutions whereas soap are not effective due to formation of insoluble fatty acids.
(iii) Non-ionic detergents: Some of the detergents are non-ionic, like the esters of high molecular mass formed by reactions between polyethylene glycol and stearic acid.