i. Synthetic fibres are also called artificial or man-made fibres.
ii. Synthetic fibres are synthesised from raw material called petrochemicals.
iii. Like synthetic fibres, plastic is also a polymers.
iv. Terylene is a popular polyester.
v. Polymer is made of many repeating units.
i. Thermoplastics can bent easily. True
ii. Polymers are made up of many bigger units. False
iii. PET is a very familiar form of polyester. True
iv. Polyester fabrics do not get wrinkled easily. True
v. Fabric obtained from silk fibre is very cheap. False
vi. Fabric made from polyester fibre does not get wrinkled easily. True
Ans. Rayon fiber is known as artificial silk.
Ans. Nylon is the first fully synthetic fibre.
Ans. Synthetic fibres melt on heating.
Ans. Esters are the chemicals which give fruits their smell.
Ans. 4 R principles mean Reduce, Reuse, Recycle and Recover.
Ans. Nylon fibre is strong, elastic and light. It is lustrous and easy to wash.
Ans. It is used for making electrical switches, handles of various utensils, etc.
Ans. It is used for making floor tiles, kitchenware and fabrics which resist fire.
Ans. Rayon is different from synthetic fibres because it is obtained from a natural source, wood pulp.
Ans. Nylon fibres are very strong as it is used to make parachutes and ropes for rock climbing.
Ans. Polythene (Poly + ethene) is a type of plastic that is used for making commonly used polythene bags.
Ans. Plastic bag is non-biodegradable because it takes several years to degenerate.
Ans. We can store jams and pickles in plastic containers because plastics do not react with water and air and do not get corroded easily.
Ans. All plastics do not have the same type of arrangement of units. In some it is linear, whereas in others it is cross-linked.
Ans. Nylon is called fully synthetic fibre because it is prepared from coal, water and air.
Ans. Polyester (Poly+ester) is actually made up of the repeating units of a chemical called an ester.
Ans. Acrylic is used as a substitute of natural wool for knitting sweaters, shawls, blankets etc.
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