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What could be, Things made of, Why/Why not?, used instead?, natural materials., QuiCK Brushup, Clay and rubber, for example, are natural plastic materials., Plastics are non-biodegradable., Mixed fibers are combinations of synthetic and natural fibers., Adhesives are things used for sticking., Look around your house and write the names of three things made of synthetic materials (for example, pencil box)., Exercise Time, Tick (/) the correct answer:, 1., Which of these is correct?, (a) All plastics can be recycled., (b) Plastics cannot be recycled., (c) Some plastics can be recycled., Plastics pollute the environment because they are:, (a) non-biodegradable, (b) eatenby animals, 2., (c) easily dissolved in rainwater., 3., Mixed fibers are combinations of :, (a) yarns, (b) plastics, Synthetic adhesives are better than natural adhesives because they:, (c) synthetic and natural fibers, 4., (a) are stronger, (b) are colourless, (c) do not dissolve in water, Fill in the blanks:, 2, Clay and rubber, recycled, suffers, Mixed fibers,, 1May and aubỐT e,, 2., for example, are natural plastic materials., Many kinds of plastics can be reey cles, The health of workers in plastic factories also Sufers, Mixed Gb have some qualities that make them better than natural fibers., 75 Science-5

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Misced fibrers., 5., Write True or False:, Electricity does not pass through plastics., Plastics are easily affected by chemicals., Clothes made of synthetic fibres should be worn in summer., 1., 2., 3., Clay and rubber are natural plastic materials., Nylon and acrylic fade very easily., 4., 5., Answer the following questions:, What are synthetic materials? Name one., Name three things that are used to make synthetic materials., 1., 2., 3., What is a plastic material?, Mention three properties that make plastics so useful., How is synthetic yarn made?, 4., 5., 6., Mention one disadvantage (bad quality) of synthetic fibres., Fun Time, Collect some pictures of synthetic materials and, paste them., astics are cheap but still they are harmful for environment. Why?, HOTS, Activity Time, sk your tailor for bits of different kinds of fabric (cloth). Stick them in your scrapboo, rite whether they are made from natural, synthetic or mixed fibres., 76 Science-5