Define the following terms and give examples. (a) Antibiotics and (b) Tranquillizers. acid dyes and basic dyes.

 Define the following terms and give examples.
(a) Antibiotics and (b) Tranquillizers.
Ans. : (a) Antibiotics :- The substances which are prodcued by certainanicro-organisms (fungi bacteria and moulds) and use to inhibit the growth or to kill the micro-organism are known as antibiotics. Penicillin was the first antibiotic which was discovered by Fleming in 1929. Chloramphenicol is a broad spectrum antibiotic. Chloramphenical is used to cure actute fever, typhoid, urinary infection and dysentry etc.
(b) Tranquillizers :- These are the substances which effect the central nervous systern and cure mental diseases. They have the sedative and calming effect but do not induce sleep. But if any drug induces sleep also, it is known as hypnotics. Both tranquillizers and hypnotics are present in sleeping pills. Some important tranqiiillizers are reserpine, luminal and seconal.

 What is the difference between acid dyes and basic dyes.

Acid Dye
1. They contain sodium salt oforganic acids, such as sulphonic acid, car- boxylic acid and phenols.
2. They are used for dyeing natural silk, wool and nylon but cannot dye cot- ton fibre.
3. The acidic groups serve as reactive points for fixing the dye to the fibre
4. Examples: Methyl orange, Methyl red.

Basic Dye

They contain the salt of organic bases i.e., - NH2 group, - NR2 group.

They are used to dye nylon , wool, leather, paper, polyester as well as cotton.

in acidic solution, the cations of -

or -NR2 groups are the reactive sites and are used to attach to the fabric.

Examples: Malachite green.