NCERT Class VIII Science Solution: Chapter 3-Synthetics Fibres and Plastics Part 5 (For CBSE, ICSE, IAS, NET, NRA 2022)

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Question 12:

‘Avoid plastics as far as possible’ . Comment on this advice.

Answer:

Now a days, plastics become very important in our daily life, even though we should avoid them as far as possible as for the following reasons:

  • Plastics are non-biodegradable and take a lot of time to decompose.
  • Plastics are not eco-friendly. By burning plastics, poisonous fumes are released that cause air pollution.
  • Sometimes cows and other animals may eat plastics present in the garbage which may choke their respiratory system and even cause death.
  • The plastic left in the soil results in soil pollution.
  • Plastic bags drained into the water bodies cause threat to the aquatic life also.
  • Polybags choke the drains and sewage pipes thus causing lot of trouble.

Question 13:

Match the terms of column I correctly with the phrases given in column II.

Match the Terms of Column I Correctly with the Phrases Given in Column II
Column IColumn II
PolyesterPrepared by using wood pulp
TeflonUsed for making parachutes and stockings
RayonUsed to make non-stick cookware՚s
NylonFabrics do not wrinkle easily

Answer:

Match the Terms of Column I Correctly with the Phrases Given in Column II. (A)
Column IColumn II
PolyesterFabrics do not wrinkle easily
TeflonUsed to make non-stick cookware՚s
RayonPrepared by using wood pulp
NylonUsed for making parachutes and stockings

Question 14:

‘Manufacturing synthetic fibres is actually helping conservation of forests’ . Comment.

Answer:

Synthetic fibres are man-made fibres. These fibres are made from petrochemicals. For manufacturing synthetic fibres cutting of trees or killing of animals is not required and we can conserve our natural environment using synthetic fibres.

Hence, ‘manufacturing synthetic fibres is actually helping conservation of forests’

As Showing Images is a Result for Manufacturing Synthetic Fi …

Question 15:

Describe an activity to show that thermoplastic is a poor conductor of electricity.

Answer:

Take a small piece of thermoplastic material and connect it between the circuit as shown in the figure. When we connect conductor in the circuit, current passes through it and the bulb glows but if we connect thermoplastic in the circuit, no current passes and the bulb does not glow.

This Image Shows Thermoplastic is a Poor Conductor of Electr …

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