Explain the following terms with suitable examples.
Anionic detergents

Explanation

Anionic detergents. This is the most important class of synthetic detergents and is widely used in home and industry (soap is also an anionic detergent, but is natural i.e., not synthetic). These are sodium salts of sulphonated long chain alcohols or hydrocarbons. Alkyl liydrogen sulphates are formed by treating long chain alcohols with conc. `H_2SO_4` and neutralising the product with aqueous NaOH. Similarly, alkyl benzenes on sulphonation with conc. `H_2SO_4` or oleum gives mainly p-derivative. This on neutralisation with NaOH(aq) for another class of anionic detergents.