CLASS-VIII
SYNTHETIC FIBRES AND PLASTICS
ASSIGNMENT-7
Q1. Fill in the blanks:
a) Synthetic fibres are also called _______________ or ______________ fibres.
b) Terycot is a mixture of _________________ and _______________.
c) ___________ is used for making bottles of soft drinks, oils etc.
d) ______________ was the first man-made plastic.
e) Thermosetting plastics have a __________________ arrangement of molecules.
f) Teflon is a ________________ plastic.
g) _______________ is a flame resistant plastic.
Q2. Match the following:
1. Terylene a) Prepared by using wood
pulp
2. Teflon b) Used for making
parachutes and stockings
3. PET c) Fabrics do not wrinkle
easily
4. Rayon d) Used to make non-stick
cookwares
5. Nylon e) Used for making magnetic
tapes
Q3. Synthetic fibres are not considered environment friendly. Why?
Q4. What do you understand by high tensile strength?
Q5. Define polymerization.
Q6. Why synthetic fibres are used for making dress materials?
Q7. a) What is the other name of artificial silk?
b) How is it prepared?
c) Why is it also called regenerated fibre?
Q8. Explain the difference between:
a) thermoplastic and thermosetting plastic
b) biodegradable and non-biodegradable materials
Q9. Write 3 uses of melamine.
Q10. Why is Teflon used to make non-stick cookwares?
Q11. Explain why the following are made of thermosetting plastics:
a) Saucepan handles
b) Electric plugs/ switches/ plug boards
Q12. Why is melamine coated on uniform of fireman?
Q13. Why electrical wires have plastic covering? OR
Why handles of screw drivers are made of plastic?
Q14. Explain why plastic containers are favoured for storing food?
Q15. Write any 2 measures that can be taken to control the damage caused by plastic waste.
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