NCTB Class 9-10 Science Chapter 6 “Polymer” Solution
Bangladesh Board Class 9-10 Science Solution Chapter 6 Polymer Solution Exercises Question and Answer by Experienced Teacher.
NCTB Solution Class 9-10 Chapter 6 “Polymer”:
|NCTB Bangladesh Board|
9 – 10 (Nine – Ten Classes)
Chapter 6 “Polymer”
Multiple choice questions
1) What type of fiber required heckling?
a) Jute b) wool
c) silk d) linen
2) The characteristics of the fiber shown on the right is
i) It is very thin.
ii) it is very cheap.
iii) it warms quickly
Which of the following is correct ?
a) i And ii b) i and iii
c) ii and iii. d) I, ii, and iii
Answer:- b) I and iii
From the diagram given below answer the question 3 and 4
1) What will be produced in fig. B ?
a) Resin b) polythene
b) melamine d) abestos
Answer:- b) polythene
2) Which of the following fiber is similar to the product in fig. B?
a) Silk. b) wool
c) hair. d) polyester
Que.1] Arju was going to school in early morning in January. he wore two shirt both made up of cotton. He remembered that 3 months ago when he wore, even one shirt he did not suffer from this type of problem.
1) What is Non- cellulosic fiber?
Answer:- some artificial fibers such as nylon , polyester, poly propylene , dacron etc. Prepared from the chemicals other than cellulose are called non- cellulosic fibers.
2) Why linen is called a natural fiber ?
Answer:- cloths are produced from yarn and yarn Is produced from the fibers which consists of smaller filaments. Basically fibers are filament. These are categorised according to their source. Linen which are naturally abundant that’s why it is called natural fiber.
3) Explain what type of clothes arju should wear?
Answer:- arju should use woolen cloths. wool is thermally non conductive and that is why widely use in winter season. As it is non conductive heat can not be conducted from body in winter. It is very old fiber and produced from different species of sheep.
4) Rationalize the fact that although Cotton is comfortable in summer it is not comfortable in winter ?
Answer:- The higher thermal conductivity of cotton fiber results in quicker dimensions of heat produced in human body. Moreover the space or pores in the yarns in cotton are wider compared with other fibers allowing easier air passing which gives comfort.
Que.2] Mr. Milan has a PVC pipe manufacturing industry. He ask emon and manum to supply raw material. Raw material supplied by the emon was elastic and receive to oxygen and moisture the physical property of the material supplied by mamon is that it can be given any shape by molten state but it is chemically inert. Both the material were non – biodegradable in soil.
A) What is monomer?
Answer:- monomeris defined as the simple molecule with two or more binding sites by which it forms the linkage with the other monomer molecule to form the polymer.
The process of making polymer from monomer is known as polymerization.
B) Why melamine is called a polymer ?
Answer:-If many small monomers are joined together to form a large chain or object is called as a polymer. Household melamine items are basically made up of melamine resin and formaldehyde monomers. Thus melamine is called as a polymer.
C) How do the materials supplied by Emon & Mamun damage environment balance ? Explain.
Answer:- The material supplied by the emon and mamun was of plastic and rubbers. Majority of the plastics and rubbers are not biodegradable. So if they are discharged as waste without recycling they accumulate in the nature and cause lots of problems. Accumulation of these materials in stage, block the sewerage lines stopping the glow of the waste water results in the water logging on roads upon rainfall. Discharged plastic in the water bodies may contaminate fish flesh. When we take meat or fish those accumulated plastic and rubber enter into the human body and may cause diseases like cancer. So it is clear that, material supplied by the manum and emon leads to environmental imbalance.
D) Which raw materials will you suggest for Mr. Milon to manufacture PVC pipe ?
Answer:-the material supplied to mr. Milon to manufacture PVC pipe were non-biodegradable in soil. But PVC is formed by the plastic material that can be easily molded. In molten condition plastic can be given any shape. All the plastic materials are polymer. The material which is used in PVC pipe soften on heating and when cooled they harden. These plastic are called thermoplastic. Which is used for PVC pipe.