(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. Cetyltrimethylammonium bromide is a popular cationic detergent and is used in hair conditioners.
Cationic detergents have germicidal properties and are expensive, therefore, these are of
limited use.
(ii) Food Preservatives: These are the chemical substances which are added to the food materials to prevent their spoilage due to microbial growth and to retain their nutritive value for long periods. Preservatives prevent the rancidity of food and inhibit growth or kill the microganisms The most-common preservations used are, sugar table salt, sodium benzoate, Sodium metabisulphite sorbic acid and propanoic acid.
(iii) Analgesics: Drugs which reduce or abolish pain without causing impairment of consciousness, mental confusion, incoordination or paralysis or some other disturbances of nervous system. These are classified as follow.
(a) Non-narcotic (non-addictive) analgesics: Aspirin, paracetamol etc.
(b) Narcotic drugs: These are known to be habit forming, e.g., morphine, Codeine, Heroin etc.
