QUALITY LEARNING MATERIAL BY ilearnsnap.com ABOUT CLOTH FIBRES AND POLYMERS CBSE

1. Is rayon a purely
synthetic fabric?

2. ● Rayon is made using
wood pulp and
chemicals.
● So, Rayon is not a purely
synthetic fabric.

3. What are the other
names of synthetic
fibres?

4. Synthetic fibres are
also called artificial
fibres or manmade
fibres

5. What are
petrochemicals?

6. The substances
refined out of
petroleum/crude oil

7. What do you
mean by fibres
used in textiles?

8. Fibres are soft, fluffy,
thin, hair-like strands
used to make yarn

9. Give some
examples of
natural fibres.

10. Natural fibres from:
● Plants - Cotton, Jute
● Animals - Silk, wool

11. What are some
examples of
synthetic fibres?

12. Rayon, Nylon, Polyester, Acrylic,
Polyethylene terephthalate
(PET), Polycot, Polywool,
Terylene, Terrycot, etc.

13. What do you mean
by a polymer?

14. ● Poly means many
● Mer means Parts
● Many identical repeating
molecules (units)
connected in long chains

15. Give an example of a
polymer found in
nature.

16. ● Cellulose is a natural
polymer is made up of
many glucose units.
● Cellulose polymer is
present in cotton.

17. What is the other
name of rayon?
Why?

18. Artificial silk is another
name of rayon because
it is as shiny as silk

19. What are the
properties of
rayon?

20. ● It is shiny like silk
● It can be dyed in
different colours
● It is cheaper than silk

21. How is rayon
made?

22. Rayon is made by
treating wood pulp
with chemicals.

23. Is rayon purely
synthetic?

24. No, Rayon is not purely
synthetic because it is
made of wood pulp and
chemicals.

25. Where is
rayon used?

26. Rayon is used to
make bedsheets,
carpets, curtains etc.

27. When was nylon
first made?

28. Nylon was first
made in 1931

29. What are the raw
materials used to
make nylon?

30. Nylon is made
using coal, water
and air.

31. Where is
nylon used?

32. Nylon is used in ropes,
parachutes, straps, bags, seat
belts, sleeping
bags,toothbrushes, tents etc.

33. Show that nylon
is very strong.

34. ● Hang weight pans using thin
strings of cotton, wool, silk and
nylon.
● Add weights to all pans, one by
one.
● Nylon carries the highest amount
of weight before breaking

35. What are some
uses of
polyester?

36. Easy to wash wrinkle
free clothes are made
using polyester

37. By what property can we
easily determine the
presence of an ester?

38. Ester is a
substance with a
sweet, fruity smell.

39. Where is PET
material used?

40. PET is used to make
bottles, utensils,
wires, films, fibres
etc.

41. Define polycot,
polywool and
terrycot.

42. ● Polycot - Combination of
polyester and cotton
● Polywool - Combination of
polyester and wool
● Terrycot - Combination of
terylene and cotton

43. Where is
acrylic used?

44. Sweaters, shawls,
blankets can be
made of acrylic.

45. Why should we
not use synthetic
fibres in kitchen?

46. Synthetic fibres catch
fire easily, melt and
stick to the body

47. What are the
advantages of
synthetic fibres?

48. Synthetic fabrics are
durable, easy to wash, easy
to dry, water resistant, low
cost, can be dyed in
different colours, stronger

49. What category do
plastics fall
under?

50. Basically, plastics
are polymers

51. What are the 2
types of plastics
based on linkages?

52. ● Linear chain plastics
● Cross linked plastics

53. What are the
advantages of
plastics?

54. ● We can recycle and reuse plastics
● We can store chemicals because they are very
less reactive
● They are light weight and strong
● They are durable
● They do not conduct electricity
● They are cheap
● They save trees and environment if we recycle
them properly
● Can be used to make different shaped parts

55. What are some
applications of
plastics?

56. ● Fire proof plastics for firemen
● Non stick materials like teflon
● Plastics that can be used in
microwave oven
● Packaging, medical
equipments, gloves, stitches
etc.

57. What is
polythene?

58. Polythene is a plastic
made up of many
repeating ethene
units or molecules

59. What is the
structural formula
of ethene?

60. ● A hydrocarbon (C2
H4
)
with 2 carbon atoms
connected by a double
bond (=)
● H2
C=CH2

61. Where is
polythene
commonly used?

62. Polythene is
commonly used to
make polythene bags

63. What are some
properties of
melamine?

64. Melamine-
1. Is fire resistant
2. Can tolerate heat

65. Where is
melamine
commonly used?

66. Melamine is used to
make switch boards,
utensil handles,
kitchenware etc.

67. What are the types
of plastics based on
remoldability?

68. ● Thermoplastics can be
heated and remolded
again using force
● Thermosetting plastics
cannot be remolded again

69. What are some
examples of
themoplastics?

70. ● Polythene
● PVC (Polyvinyl
Chloride)

71. What are the
examples of
themosetting plastics?

72. ●Bakelite
●Melamine

73. What are some
useful properties of
bakelite?

74. Bakelite is a poor
conductor of
electricity and heat.

75. Where is bakelite
used?

76. Bakelite is used in
switch boards and
handles of utensils.

77. What are biodegradable
and non biodegradable
materials?

78. ● Biodegradable materials
decompose easily by action of
microbes e.g. paper, wood,
kitchen waste
● Non biodegradable materials do
not decompose easily by action
of microbes e.g. plastics, glass

79. What are some
disadvantages of
plastics?

80. ● Poisonous fumes are produced
when plastic is burnt
● Plastic garbage clogs drains
and kills animals
● Plastic does not decompose
over a short time

81. How can we solve
the problem of
plastic garbage?

82. ● Reduce the use of plastic bags
● Reuse the plastic bags again
● Recycle very old plastic bags
● Recover plastic materials from garbage
● Refuse to use unrecyclable plastic bags
● Do not throw plastic waste outside the
dustbin

83. How is yarn
made?

84. Yarn or thread is
made by spinning
clothing fibres

85. What do you
mean by spinning?

86. Twisting fibres together,
using a spinning wheel,
to produce yarn/thread

87. What do you mean
by plucking, in
cotton industry?

88. Removing cotton
bolls from the
cotton plant

89. What do you
mean by ginning?

90. Removing seed
from the cotton
boll

91. What do you
mean by shearing?

92. Removing the coat
of hair on an animal
like sheep

93. What do you mean
by deburring?

94. Removing useless
fluffy burrs from
the fibres

95. What do you mean
by ‘scouring’ cloth
fibres?

96. Washing away dust
and grease from
cloth fibres

97. What do you
mean by sorting of
fibres?

98. Separating different
types/textures of
fibres

99. What do you
mean by grading?

100. Separating
different
qualities of fibres

101. What do you
mean by carding?

102. Arranging, rolling and
straightening of
fibres, before spinning

103. What do you
mean by dyeing?

104. Adding colour to
fibres

105. What do you mean
by weaving?

106. Arranging yarns to
make fabric (cloth
material)

107. What do you mean
by tailoring?

108. Cutting and stitching
fabric to make
clothes

109. What do you mean
by sericulture?

110. Rearing of silkworms
to get silk fibres

111. What do you mean
by reeling of fibres?

112. Pulling out silk
fibres from
cocoons

113. What do you
mean by retting?

114. Submerging a bundle
of jute stems under
water, for a long time

115. What do you
mean by rearing?

116. Growing and maintaining
animals to obtain some
natural resource

117. Write some
sources of wool.

118. ● Camel, Alpaca camel, llama,
sheep, goat
● Angora goat (found in
Jammu and Kashmir)
● Yak (found in Tibet, Ladakh)

119. What do you
mean by fleece?

120. Fleece is the hair of
animals like sheep or
yak

121. Why does wool
keep us warm?

122. ● Wool has air pockets
● Air is a bad conductor of
heat
● So, wool does not allow
our body heat to escape

123. What are the 2 types
of sheep hair based
on quality?

124. ● Coarse (rough) beard hair
● Fine (soft) under-hair

125. What do you mean
by selective
breeding?

126. ● Selecting suitable parent
breeds to obtain better quality
and quantity of a natural
resource
● E.g. To obtain large quantity of
white wool or large quantity
milk

127. Give some sheep
rearing locations
in India.

128. ● Hills of Jammu & Kashmir,
Himachal Pradesh,
Uttaranchal, Arunachal
Pradesh and Sikkim
● The plains of Haryana, Punjab,
Rajasthan and Gujarat

129. What do you
mean by fodder?

130. Food given to domestic
herbivores like cow,
goat, sheep etc.

131. What kind of fodder
is given to sheep?

132. ● Sheep graze on grass and
leaves.
● They are given pulses, corn,
jowar, oil cakes, and minerals
● During winter, they are
provided grass, leaves, dry
fodder and grains, indoors.

133. In which season are
sheep usually
sheared?

134. Sheep are sheared in
hot summer season

135. What causes wool
sorters disease?

136. Wool sorters disease is a fatal
blood disease, caused by
anthrax bacteria, found in
sheep hair

137. Describe the life
cycle of a silk moth.

138. ● Adult female silk moth lays around
300 eggs
● The larva/caterpillar eat mulberry
leaves for around 25 days
● At the pupa stage they spin cocoon
around themselves
● Adult silk moth grows and breaks out
of the cocoon

139. Describe the activities
of sericulture.

140. ● Adult female moth lays around 300 eggs (eggs are
spread on cloth or paper and given the correct
humidity and temperature)
● Larvae eat mulberry leaves for around 25 days
(Larvae are kept in bamboo trays with mulberry
leaves)
● At pupa stage they spin cocoon around
themselves (Pupa attach themselves to small
twigs in the tray)
● Cocoons are sun dried, boiled or steamed
● Silk fibres are reeled from the cocoon