Question

Why is it not advisable to wear synthetic clothes while bursting fire crackers?
(i) All synthetic fibres are prepared by using raw materials of petroleum origin.
(ii) Synthetic fibres catch fire easily.
(iii) On heating, synthetic fibres melt and stick to the body of the person wearing it.
(A) (i) only
(B) (ii) only
(C) (i) and (iii)
(D) (ii) and (iii)

Answer 1

Hint: Synthetic fibres i.e. nylons tend to melt rather than burn on heating and the ease of ignition can be determined by the thermo-plasticity of the substance. And therefore, the risk of severe fire burns is higher with nylon than cotton.

Complete step-by-step answer:
Synthetic fibres are man-made. Fibres that are prepared from raw material petroleum known as petrochemicals. All fabrics are generally obtained from fibres, while fibres are obtained from man-made sources. They consist of a small unit or a polymeric chain which is made from many repeating units called monomers. For example, nylon, acrylics, polyurethane, and polypropylene.
There are many advantages of synthetic fibres. They are very durable and do not wrinkle easily if used for clothes. They are elastic and can be easily stretched. They are strong i.e. can sustain heavy load and also soft, used in clothing materials.
But there are few disadvantages also. They are cheaper than the natural fibres. They do not absorb water and get affected if washed by hot water. They catch fire more easily as compared to any other natural or artificial fibres.
The material of synthetic fibre is thermoplastic in nature. Thermoplastic materials are those polymers that can be easily melted and moulded indefinitely on heating and harden up on cooling. When frozen, they become glass like and can be broken. Due to its this property, clothes made from synthetic fibres become hazardous and dangerous if brought near fire.
From all this information, we confirm that it is not advisable to wear synthetic clothes while bursting fire crackers because they catch fire easily and on heating, synthetic they melt and stick to the body of the person wearing it.

Hence, the correct option is (D).

Note: Option (A) is wrong because its petroleum origin is not responsible for its melting cause. When polymer melts, the bonds between chains break first but the monomeric bonds remain intact. Synthetic fibres do not easily take up colours like natural fibres.