Give one word for the following statements - Polymer which is light and soft like wool…………
Answers
Answer:
cotton is your answer it will help you
Question. 1 Pick the synthetic fibre out of the following.
(a) Cotton (b) Nylon (c)Jute (d)Wool
Answer. (b) Nylon Is a synthetic fibre. It is made without using any natural raw material. Cotton, jute and wool are natural fibres.
Question. 2 Which of the following is a source of rayon?
(a) Wool (b) PET (c) Wood pulp (d) Silk
Answer. (c) Wool pulp
Rayon is obtained by the chemical treatment of wool pulp (which contains cellulose).
Question. 3 Polycot is obtained by mixing
(a) nylon and wool (b) polyester and wool
(c) nylon and cotton (d) polyester and cotton
Answer. (d) Polycot is obtained by mixing polyester and cotton.
Polycot = polyester + cotton
Question. 4 Which is a thermosetting plastic?
(a) Melamine (b) Polythene –
(c) PVC (d) Nylon
Answer. (a) Melamine is a thermosetting plastic which when moulded once, cannot be softened by heating.
Question. 5 The material similar to silk in appearance is
(a) nylon (b) rayon
(c) polyester (d) terylene
Answer. (b) Rayon resembles silk in appearance, therefore, rayon is also called artificial silk.
Question. 6 The most suitable material for the preparation of handles of cooking utensils is (a) polythene (b) PVC
(c) nylon (d) bakelite
Answer. (d) Bakelite is used for making the handles of various cooking utensils because it is a poor conductor of heat and does not become soft on getting heated.
Question. 7 Which of the following is not a common property of plastics?
(a) Non-reactive
(b) Light in weight
(c) Durable
(d) Good conductor of electricity
Answer. (d) Plastics are non-reactive, light in weight and durable but they do not conduct electricity.
Question. 8 Which of the following represents the correct match for items in Column A with those in Column B.
ncert-exemplar-problems-class-8-science-synthetic-fibres-and-plastics-1
Codes
(a) (a)-(ii), (b)-(iii), (c)-(i)
(b) (a)-(iii), (b)-(i), (c)-(ii)
(c) (a)-(ii), (b)-(i), (c)-(iii)
(d) (a)-(iii), (b)-(ii), (c)-(i)
Answer. (c) Nylon —-> Fibre , PVC —->Thermoplastic , Bakelite —->Thermosetting plastic
Question. 9 Which of the following groups contains all synthetic substances?
(a) Nylon, tprylene, wool
(b) Cotton, polycot, rayon
(c) PVC, polythene, bakelite
(d) Acrylic, silk, wool
Answer. (c) PVC, polythene and bakelite are synthetic substances.
Question. 10 The material which is commonly used for making kitchen containers is
(a) PVC (b) acrylic
(c) teflon (d) PET
Answer. (d) PET is ‘poly-ethylene’ terephthalate’ PET as a plastic is very light weight and is commonly used for making kitchen containers.