Synthetic Fibres and Plastics quiz

Rayon is obtained from:

The first fully synthetic fibre was:

Which of these is a thermosetting plastic?

Which fibre is used to make sweaters as a substitute for wool?

PET is a type of:

Cotton is a polymer of:

Which property of nylon makes it suitable for parachutes and climbing ropes?

Which of these is non-biodegradable?

Melamine is used to coat the uniforms of firemen because it:

The handles of frying pans are made of bakelite because it is:

Name two uses of nylon and two uses of polyester. (2 marks)

Why is polyester preferred for dress material? (2 marks)

Why are plastic containers used for storing food and chemicals? (2 marks)

Why should plastic waste not be burnt? (2 marks)

Why does PVC soften on heating while bakelite does not? (2 marks)

What is meant by Terylene? Give one use. (2 marks)

How do plastic bags harm cows and other animals? (2 marks)

What is the source of raw materials for most synthetic fibres? (2 marks)

Give two advantages and two disadvantages of synthetic fibres. (2 marks)

What should be done to reduce plastic pollution? Give two habits. (2 marks)

A shopkeeper gives away 120 plastic bags a day. In how many days will he give away 3,600 bags? If he charges Rs 5 for a cloth bag and sells 40 cloth bags a day, how much does he earn from them in 30 days? (3 marks)

In a thread-strength activity, the threads broke at the following loads: cotton 2.5 kg, wool 1.5 kg, silk 4 kg, nylon 10 kg. Arrange them in increasing order of strength and find how many times stronger nylon is than wool. (3 marks)

A city produces 500 tonnes of solid waste a day, of which 12% is plastic. How much plastic waste is produced daily? How much in a 30-day month? (3 marks)

A polymer chain is made of 5,000 identical monomer units, each of mass 28 units. Find the total mass of the chain in units. (3 marks)

Out of 60 items in a kitchen, 18 are made of plastic, 24 of metal, 12 of glass and 6 of wood. Find the percentage of plastic items and of wooden items. (3 marks)

Read the passage and answer the questions. Seema was cooking in a nylon dress when her sleeve caught fire. The fabric melted and stuck to her skin, causing severe burns. Her mother had always told her to wear cotton in the kitchen. (i) Why did the fabric melt and stick to her skin? (ii) Why is cotton safer in the kitchen? (iii) What other precaution should be taken while cooking? (5 marks)

Read the passage and answer the questions. A survey of a beach found plastic bottles, bags and fishing nets everywhere. Turtles and fish were found entangled in the nets, and some seabirds had plastic in their stomachs. (i) Why does plastic remain on beaches for so long? (ii) How does plastic harm marine animals? (iii) Suggest two ways to reduce this pollution. (5 marks)

Read the passage and answer the questions. A company collects used PET bottles, melts them and makes them into fibres used for jackets and carpets. However, it cannot recycle broken bakelite switches the same way. (i) What type of plastic is PET? (ii) Why can PET be recycled by melting? (iii) Why can bakelite not be recycled in this way? (5 marks)

Read the passage and answer the questions. A raincoat, a tent and an umbrella are made of polyester or nylon-coated fabrics. They keep the user dry, are light and last long. (i) Which property makes them suitable for rainwear? (ii) Why do synthetic fabrics dry quickly? (iii) Name one disadvantage of these fabrics. (5 marks)

Read the passage and answer the questions. Many states in India have banned single-use plastic carry bags. Shoppers now carry cloth or jute bags. Some vendors still use thin polythene bags secretly. (i) Why have single-use plastic bags been banned? (ii) Why are jute and cloth bags better for the environment? (iii) What can students do to support the ban? (5 marks)

Draw diagrams to represent a polymer chain of cellulose made of glucose units and of a synthetic polymer. Explain what polymers are and describe rayon, nylon, polyester and acrylic with one use each. (6 marks)

Draw diagrams showing the arrangement of polymer chains in thermoplastics and thermosetting plastics. Explain their differences with two examples and two uses of each. (6 marks)

Draw a labelled diagram of an activity to compare the strength of different fibres. Describe the procedure and the expected observations. (6 marks)

Draw a flowchart showing the life cycle of a plastic bottle from manufacture to disposal or recycling. Explain the harmful effects of plastic waste at each stage of disposal. (6 marks)

Make a poster with sketches promoting the 5 R principle for plastics. Explain each R with a practical example from daily life. (6 marks)