Synthetic fibers and plastics are made up of molecules called polymers. PET is a ______ These are those substances that cannot be decomposed by microorganisms in natural way. Fabric made from polyester does not get wrinkled easily. How can you show that thermoplastics are poor conductors of electricity? Why has artificial wool become more popular than natural wool?Â, Artificial wool is prepared from another type of synthetic fiber called acrylic. hich of the following is a natural fiber? What are natural and synthetic polymers? In this way, we can find out the water absorbing tendency of different fibers. Definition of Thermosetting Plastic. It is highly resistant to insects, fungi, animals, chemicals, etc. Synthetic fibers are synthesized from raw material called ……….. Like synthetic fibers, plastic is also a ……….. Give examples which indicate that nylon fibers are very strong. They have caused many health and environmental hazards. CBSE Class 8 Science Lessons Explanation, Notes, NCERT Question Answers, ← Crop Production and Management Class 8 CBSE Science Notes, Question Answers, Microorganisms Class 8 Notes, Question Answers →, Chapter 1 How, When and Where Class 8 History Explanation, Question Answers, Chapter 2 From Trade to Territory – The company establishes power Class 8 History, Explanation, Question Answers, Chapter 3 Ruling the Countryside Class 8 History Explanation, Question and Answers, Chapter 4 Tribals, Dikus and the Vision of a Golden Age Class 8 History Explanation, Chapter 5 When people rebel – 1857 and after Class 8 History Explanation, Chapter 6 Weavers Iron Smelters and Factory Owners Class 8 History, Explanation, Chapter 1 The Indian Constitution, Class 8 Civics Explanation, Question and Answers, Chapter 2 Understanding Secularism, Class 8 Civics Explanation, Question and Answers, Chapter 3 Why do we need a Parliament, Class 8 Civics Explanation, Question and Answers, Chapter 4 Understanding laws, Class 8 Civics Explanation, Question and Answers, Chapter 5 Judiciary Class 8 Civics Explanation, Question and Answers, Chapter 6 Understanding Our Criminal Justice System Class 8 Civics Explanation, Question and Answers, Chapter 7 Understanding Marginalization, Class 8 Civics Explanation, Question and Answers, Chapter 8 Confronting Marginalisation, Class 8 Civics Explanation, Question and Answers, Chapter 9 Public Facilities, Class 8 Civics Explanation, Question and Answers, Chapter 10 Law and Social Justice, Class 8 Civics Explanation, Question and Answers, Chapter 1 Resources, Class 8 Geography lesson Explanation, Question and Answers, Chapter 2 Land, Soil, Water, Natural Vegetation and Wildlife Resources, Class 8 Geography Lesson Explanation, Question and Answers, Chapter 3 Mineral and Power Resources, Class 8 Geography lesson Explanation, Question and Answers, Chapter 4 Agriculture, Class 8 Geography lesson Explanation, Question and Answers, Chapter 5 Industries, Class 8 Geography lesson Explanation, Question and Answers, Chapter 6 Human Resources, Class 8 Geography lesson Explanation, Question and Answers, Chapter 1 Crop Production and Management Class 8 CBSE Science Notes, Question Answers, Chapter 2 Microorganisms Class 8 Notes, Question Answers, Chapter 3 Synthetic fibres and Plastics Class 8 Notes, Question Answers, Chapter 4 Metals and Non Metals Class 8 Notes, Question Answers, Chapter 5 Coal and Petroleum Class 8 Notes, Question Answers, Chapter 6 Combustion and Flame Class 8 Notes, Question Answers, Chapter 7 Conservation of plants and animals Class 8 Notes, Question Answers, Chapter 8 Cell Structure and Function Class 8 Notes, Question Answers, Chapter 9 Reproduction Class 8 Notes, Question Answers, Explanation, Chapter 10 Reaching the age of adolescence Class 8 Notes, Question Answers, Explanation, Chapter 11 Force and Pressure Class 8 Notes, Question Answers, Explanation, Chapter 12 Friction Class 8 Notes, Question Answers, Explanation, Chapter 13 Sound Class 8 Notes, Question Answers, Explanation, Chapter 14 Chemical Effects of Electric Current Class 8 Notes, Question Answers, Explanation, Chapter 15 Some Natural Phenomena Class 8 Notes, Question Answers, Explanation, Chapter 16 Light Class 8 Notes, Question Answers, Explanation, Chapter 17 Stars and the Solar System Class 8 Explanation, Notes, Examples, Question Answers, Chapter 18 Pollution of Air and Water Class 8 Explanation, Notes, Examples, Question Answers, Chapter 1 Dhwani Class 8 Summary, Explanation, Question Answers, Chapter 2 Lakh Ki Chudiyan Class 8 Summary, Explanation, Question Answers, Difficult Words, Chapter 3 Bus Ki Yatra Class 8 Summary, Explanation, Question Answers, Chapter 4 Deewano ki Hasti Class 8 Summary, Explanation, Question Answers, Chapter 5 Chitthiyon Ki Anoothi Duniya Class 8 Summary, Explanation, Question Answers, Chapter 6 Bhagwan Ke Dakiye Class 8 Summary, Explanation, Question Answers, Chapter 7 Kya Nirash Hua Jaye Class 8 Summary, Explanation, Question Answers, Chapter 8 Yeh Sabse Kathin Samay Nahi Class 8 Summary, Explanation, Question Answers, Chapter 9 Kabir Ki Saakhiyaan Class 8 Summary, Explanation, Question Answers, Chapter 10 Kamchor Class 8 Summary, Explanation, Question Answers, Chapter 11 Jab Cinema Ne Bolna Sikha Class 8 Summary, Explanation, Question Answers, Chapter 12 Sudama Charit Class 8 Summary, Explanation, Question Answers, Chapter 13 Jahan Pahiya hai Class 8 Summary, Explanation, Question Answers, Chapter 14 Akbari Lota Class 8 Summary, Explanation, Question Answers, Chapter 15 Surdas ke Pad Class 8 Summary, Explanation, Question Answers, Chapter 16 Pani ki Kahani Class 8 Summary, Explanation, Question Answers, Chapter 17 Baaz aur Saanp Class 8 Summary, Explanation, Question Answers, Chapter 18 Topi Class 8 CBSE Hindi Lesson, Summary, Explanation, Question Answers, Entrance Exams for Arts students after Graduation, List of Entrance Exams conducted by IGNOU. Examples of thermosetting plastics include bakelite, urea-formaldehyde resins. Therefore, it is used in hot and humid climates. Some of the plastic has linear arrangement, while some has cross linked. Main Difference – Thermoplastic vs Thermosetting Plastic. Thermosetting Plastic: Some plastics do not get deformed on heating, and cannot be re-molded into a new shape.          (a) thermoplastic polymer     (b) thermosetting polymer Which term is used for polymers made up of a large number of glucose units? Synthetic fibers are also called ……… or …….. fibers. Take a cotton thread of about 60 cm length. Then these ropes are useful in rock climbing etc. Time to check knowledge by answering the following questions-, Choose the correct option in the following questions:Â, 01. Why do mountaineers use nylon ropes for climbing the mountains? Thermosetting plastics: The plastics which when moulded once, cannot be softened by heating are called thermosetting plastics. Give an example of a biodegradable aliphatic polyester. There is a disadvantage with synthetic fibers that synthetic fibers melt on heating. Class 8; Class 9; Class 10; Class 11; Class 12; NCERT Solutions. It remains crisp and is easy to wash. Why has artificial wool become more popular than natural wool?Â, Answer: Artificial wool is prepared from another type of synthetic fiber called acrylic. It is therefore advised not to wear synthetic clothes while working in a laboratory or working with fire in the kitchen. All NCERT textbook questions have been solved by our expert teachers. })(window, document); Your email address will not be published. Answer: Cellulose Acrylic fibers are advantageous over? Polycot is a mixture of polyester and cotton. Answer: Parachutes and ropes for rock climbing which indicates that nylon fibres are strong. b. Polythene is prepared from______ .  Give an example of natural polymer? NCERT Solutions for Class 8 Science Chapter 3. These solutions for Man Made Materials are extremely popular among Class 8 students for Science Man Made Materials Solutions come handy for quickly completing your homework and preparing for exams. When you are studying polymers in chemistry you will generally come across a typical question like “distinguish between or write the differences between thermoplastic and thermosetting plastic.” While thermoset plastics and thermoplastics sound very similar, they are totally different compounds and have different properties as well as applications. d. Synthetic fibers catch fire easily so they are _______ .  Copyright © 2004 - 2020 Question 3 What are thermosetting plastics? 1. Nylon is made from ____? What are polycot and polywool? NCERT Solutions for Class 8 Science Chapter 3 – 5 Mark Questions and Answers. Polyester is actually made by repeating the units of a chemical called ester. Answers: Question: Fill in the blanks :-  c. ______ shrinks on burning producing black smoke.          (a) Toys                                 (b) Cooker handles They are manufactured using plant materials and minerals. (ii) heat resistant. […] Hence, they can be modified again and again. Name the plastic which cannot be softened once molded into a shape? These are generally used in adhesives. 1:50 2.7k + Eg:- Bakellite, Urea, Formaldehyde, Resin, etc . 13. Name the plastic used for making insulation cover of electrical wires? 01. Question 1 What are thermoplastics? We should carry cotton or jute bags for shopping. 😡😡. mountaineers use nylon ropes for climbing the mountains because. The fabric melts and sticks to the body of the person wearing it. 11. Polymers are made up of small units called _____,           (a) layers                                 (b) molecules,           (c) cells                                   (d) monomers, 04. It has capacity to bear weight and helps the mountaineers to climb. define thermoplastics and thermosetting polymers w... General Principles and Processes of Isolation of Elements. b) Bakelite is a kind of thermosetting plastic which is a bad conductor of heat and electricity. It is used in the manufacturing of various machine parts. Comment. Answer: Polyester is actually made by repeating the units of a chemical called ester. This allows the chair to remain in one shape only without getting affected by sun heat. Thermosetting and thermoplastics are two different classes of polymers, which are differentiated based on their behavior in the presence of heat.The main difference between thermoplastic and thermosetting plastic is, thermoplastic materials have low melting points; therefore, they can be remoulded or recycled by … Question 8: Define thermoplastic? Answer: Summer season. The non stick coating on pans and other cooking utensils is made from ______? Thus, we can say that thermoplastics are poor conductors of electricity. Take the pieces out of the containers after five minutes and spread them in the sun for a few minutes.          (c) nylon                                (d) thermosetting polymer, 10. Science MCQs for Class 8 Chapter Wise with Answers PDF Download was Prepared Based on Latest Exam Pattern. Question: Why has government banned the use of polythene bags ?  ______ burns vigorously and leaves little ash.Â, b. Synthetic fibers are not good absorbers of _______ .Â, c. In______ weather clothes made of synthetic fiber stick to the body.Â, d. Synthetic fibers catch fire easily so they are _______ .Â, e. Clothes made of synthetic fibers should not be worn in ______, a. Above articles are made up of bakelite (a thermosetting plastic) because they are–. nylon is a high strength fiber so it does not break easily. It is soft, smooth, cool, comfortable, and highly absorbent. Topics covered are Introduction to fibres, kinds of fibres. Answer: Three main advantages of using plastic containers for storing food are: Question: Explain why the following are made of thermosetting plastics.  Reuse: This means that we should reuse the substances that does not harm our environment and it should be biodegradable. Pieces in different mugs and each mug contains the same amount of water 12 ; Solutions. C. ______ shrinks on burning producing black smoke chair to remain in one shape only without affected. Manner on the basis of molecular forces parents in selecting these pieces like those of natural fibers set. A kind of electric shock when you touch it: write advantages of using containers! Urea ( NH2CONH2 ) required in making non stick coating on pans and other Schools you between! Re-Molded into a fcc lattice with edge length 3.61 x 10-8cm you touch it, formaldehyde, Resin etc... 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