Synthetic Fibres and Plastics
10. Give examples to show that plastics are non-corrosive in
nature.
Ans. Plastics are not corroded Example-the cleansing chemicals that we
use at home are stored in plastic bottles, instead of metal containers.
11. Should the handle and bristles of a tooth brush be made
of the same material? Explain your answer.
Ans. No. The handle of a
toothbrush should be hard and strong, while the bristles should be soft and
flexible.
12. ‘Avoid plastics as far as possible’. Comment on this
advice.
Ans.
·
Plastics are
non-biodegradable they take several years to decompose.
·
Plastics add to
the environmental pollution. They cannot be burnt as when burnt,
·
Plastic bags
thrown in the garbage dump are swallowed by animals like cows and choke their
respiratory system.
·
We should avoid
plastics as far as possible.
13. Match the terms of column A correctly with the phrases
given in column B.
|
A
|
B
|
|
(i) Polyester
|
(a) Prepared by using wood pulp
|
|
(ii) Teflon
|
(b) Used for making parachutes and stockings
|
|
(iii) Rayon
|
(c) Used to make non-stick cookware
|
|
(iv) Nylon
|
(d) Fabrics do not wrinkle easily
|
Answer
|
A
|
B
|
|
(i) Polyester
|
(d) Fabrics do not wrinkle easily
|
|
(ii) Teflon
|
(c) Used to make non-stick cookware
|
|
(iii) Rayon
|
(a) Prepared by using wood pulp
|
|
(iv) Nylon
|
(b) Used for making parachutes and stockings
|
14. ‘Manufacturing synthetic fibres is actually helping conservation
of forests’. Comment.
Ans. Raw materials for natural fibres are mainly derived from plants
and this means cutting a lot of trees. This leads to deforestation. But raw
materials of synthetic materials are mainly petrochemicals. Hence,
manufacturing synthetic fibres helps in the conservation of forests.
15. Describe an activity to show that thermoplastic is a poor
conductor of electricity.
Ans.
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