Class 8 Science Chapter 3 MCQ
Class 8 Science Chapter 3 MCQ (Multiple Choice Questions) of Synthetic Fibres and Plastic. A full revision with question-answer and explanation in the form of MCQs based on latest CBSE Syllabus for new academic session 2020-2021.After selecting the correct or incorrect answers, you can see the right answers with reason behind them.
Class 8 Science Chapter 3 MCQ for 2020-2021
|Contents:||Multiple Choice Questions – MCQ Tests|
Class 8 Science Chapter 3 MCQ for Exams
Class 8 Science Chapter 3 MCQ with complete explanation are given below. There more than 100 questions with answers based on Class 8 Science Chapter 3 NCERT Textbook. All the 20 sets of online tests are free to use again and again. If you feel revision, please visit to Important Questions or NCERT Solutions links given just below to each question.
Consider the following statements, choose the incorrect one:
In which of the following statements is or are incorrect?
Which of the following statement is or are incorrect?
Identification of fibres by burning their threads
|Cotton:||Burns completely, leaving no residue.|
|Nylon:||Burns slowly; fabric shrinks after exposure to flame, forms hard beads and gives off a smell of burning hair.|
|Wool and Silk||Burns slowly, with a smell like that of burning hair but no beads are produced.|
|Polyester||Results are like nylon, except that black smoke is produced.|
|Rayon||Burns quickly with a smell of burning paper.|
|Acrylic||Burns slowly with a sooty flame; fabric shrinks from flame, and forms black beads.|
Leftover chemical substances obtained from petroleum products were treated with sulphuric acid to invent a new soap-like product known as detergent.
What is a polymer?
A long chain of molecules is called a polymer. It is made up of a large number of monomer molecules joined end to end to form a large molecule. There are many polymers that occur naturally, such as rubber, silk, wool and even cotton.
Which is the first man made synthetic polymer?
The first man-made synthetic fibre, nylon, was put into commercial production in 1939 by a team of scientists of the famous chemical company, E.I. Dupont de Nemours. Nylon derives its name from the first letter of ‘New York’ and first three letters of ‘London’, the two cities where it was simultaneously developed and marked.
What is Rayon?
Rayon is a type of synthetic (man-made) material that resembles silk in appearance.
What are the different forms of Terylene?
Terylene has wool-like texture, which is why it is often used to weave fabrics for making suits, trousers, etc. It is called terycot when blended with cotton, and terywool when mixed with wool.