Ans. Nylon is used for making parachutes and ropes for rock climbing because nylon fibre is strong and can hold heavy weight.
Ans. Synthetic fibres and plastics, like natural fibres, are made of very large units called polymers. Polymers are made up of many smaller units.
Ans. All the synthetic fibres are prepared by a number of processes using raw materials of petroleum origin, called petrochemicals.
Ans. We should use cotton or jute bags while going for shopping in order to minimise the use of plastic bags.
Ans. Plastic articles are available in all possible shapes and sizes because plastic is easily mouldable i.e. can be shaped in any form.
Ans. Teflon is used for nonstick coating on cookwares because it is a special plastic on which oil and water do not stick.
Ans. Plastic containers are favoured for storing food because of their light weight, lower price, good strength and easy handling.
Ans. PET is a very familiar form of polyester. It is used for making bottles, utensils, films, wires and many other useful products.
Ans. Polycot is a mixture of polyester and cotton.
Polywool is a mixture of polyester and wool.
Ans. Tin, aluminium and other metal can are considered non-biodegradable because they approximately take 100 to 500 years to degenerate.
Ans. Uses rayon
i. It is mixed with cotton to make bed sheets.
ii. It is mixed with wool to make carpets.
Ans. Ways to reduce use of plastic materials
i. Avoid the use of plastics as far as possible.
ii. Make use of bags made of cotton or jute when you go for shopping.
Ans. Plastics do not react with water and air. They are not corroded easily. That is why they are used to store various kinds of material, including many chemicals.
Ans. Special plastic cookware is used in microwave ovens for cooking food. In microwave ovens, the heat cooks the food but does not affect the plastic vessel.
Ans. Plastics find extensive use in the health-care industry. Some examples of their use are the packaging of tablets, threads used for stitching wounds, syringes, doctors’ gloves and a number of medical instruments.
Ans. Melamine is a versatile material. It resists fire and can tolerate heat better than other plastics. It is used for making floor tiles, kitchenware and fabrics which resist fire.
Ans. Plastics are poor conductors of heat and electricity. That is why electrical wires have plastic covering, and handles of screw drivers are made of plastic.
Ans. Most of the thermoplastics can be recycled. However, during recycling certain colouring agents are added. This limits its usage especially for storage of food.
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