Page 1 :
Question 1., Explain why some fibres are called synthetic., , Answer:, Some fibres are called synthetic fibres because, , they are made by man using chemicals., , Scanned with CamScanner

Page 2 :
ae Mark (~ ) the correct answer., , Rayon is different from synthetic fibres because, (a) it has a silk-like appearance., , ors obtained from wood pulp., (c) its fibres can also be woven like those of natural fibres., , 3. Fill in the blanks with appropriate words., , <a” Synthetic fibres are also called MON Mode or ontificiel bres., (b) Synthetic fibres are synthesised from raw material called peoche mi tale, (c) Like synthetic fibres, plastic is also a folumey., , Scanned with CamSeanner

Page 3 :
Question 4., , Give examples which indicate that nylon fibres, are very strong., , Answer:, , The following examples indicate that nylon fibres, are very strong., , (i) They are used for making parachutes and, , ropes for rock climbing., , (ii) They are used in making seat-belts, fishing, , nets, tyre cord, a string for sports rackets and, musical instruments., , Scanned with CamScanner

Page 4 :
Question 5., , Explain why plastic containers are favoured for, storing food., , Answer:, , Plastic containers are favoured for storing food, because of the following reasons:, , (i) the plastics do not react with the food stored, in them., , (ii) the plastics are lightweight and are strong., (iii) they are easy to handle and safe., , Scanned with CamScanner

Page 5 :
QUCSUOTIO., , Explain the difference between thermoplastic, , and thermosetting plastics., , , , Answer:, Thermosetting, Thermoplastics, plastics, (i) These plastics, (i) These plastics, , softened on heating, , and can be bent easily., , (ii) They do not lose, their plasticity., , (iii) Examples are, , polyethene, PVC, etc., , when moulded once,, can't be softened, , again., , (ii) They lose their, plasticity., , (iii) Examples are, bakelite and, , melamine., , Scanned with CamSeanner