3. Synthetic Fibres And Plastics Class 8 Science [LATEST] Solutions Chapter Review in English - CBSE Study
NCERT Solutions for Class 8 Science are carefully prepared according to the latest CBSE syllabus and NCERT textbooks to help students understand every concept clearly. These solutions cover all important 3. Synthetic Fibres And Plastics with detailed explanations and step-by-step answers for better exam preparation. Each Chapter Review is explained in simple language so that students can easily grasp the fundamentals and improve their academic performance. The study material is designed to support daily homework, revision practice, and final exam preparation for Class 8 students. With accurate answers, concept clarity, and structured content, these NCERT solutions help learners build confidence and score higher marks in their examinations. Whether you are revising a specific topic or preparing an entire chapter, this resource provides reliable and syllabus-based guidance for complete success in Science.
Class 8 English Medium Science All Chapters:
3. Synthetic Fibres And Plastics
1. Chapter Review
Chapter Review:
- Fabrics are made from fibres obtained from natural or artificial sources.
- Fibres are also used for making a large variety of household articles.
- Natural fibres like cotton,wool, silk, etc., are obtained from plants or animals.
- The synthetic fibres, on the other hand, are made by human beings that is why these are called synthetic or man-made fibres.
- Many such small units combine to form a large single unit called a polymer.
- Polymers occur in nature also. Cotton, for example, is a polymer called cellulose.
- Cellulose is made up of a large number of glucose units.
- Such a fibre was obtained by chemical treatment of wood pulp. This fibre was called rayon or artificial silk.
- Rayon is mixed with cotton to make bed sheets or mixed with wool to make carpets.
- Nylon fibre was strong,elastic and light.It was lustrous and easy to wash.So ,it became very popular for making clothes and parachutes and ropes for rock climbing.
- PET is a very familiar form of polyester. It is used for making bottles,utensils, films, wires and many other useful products.
- Sweaters and shawls or blankets are prepared from another type of synthetic fibre called acrylic.
- All the synthetic fibres are prepared by a number of processes using raw materials of petroleum origin, called petrochemicals.
- Plastic can be recycled, reused, coloured, melted, rolled into sheets or made into wires.
- Polythene (Poly+ethene) is an example of a plastic. It is used for making commonly used polythene bags.
- Such plastic which gets deformed easily on heating and can be bent easily are known as thermoplastics.examples: toys, combs and various types of containers.
- There are some plastics which when moulded once, can not be softened by heating. These are called thermosetting plastics. examples: bakelite and melamine
- Plastics do not react with water and air. They are not corroded easily. That is why they are used to store various kinds of material.
- Plastic is very light, strong, durable and can be moulded into different shapes and sizes, it is used for various purposes. Plastics are generally cheaper than metals.
- Plastics are poor conductors of heat and electricity. That is why electrical wires have plastic covering, and handles of screw drivers are made of plastic.
- Teflon is a special plastic on which oil and water do not stick. It is used for nonstick coating on cookwares.
- A material which gets decomposed through natural processes, such as action by bacteria, is called biodegradable
- A material which is not easily decomposed by natural processes is termed as non-biodegradable.
- The 4 R principle is Reduce, Reuse, Recycle and Recover.
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