Polymers

Question 1

What are polymers?

Answer 1

They are large molecules that are built from many small units called monomers.

Question 2

How is a poly(ethene) formed?

Answer 2

At high temperature and pressure in the presence of a catalyst,
- one carbon-carbon double bond in each ethene monomer will break
- each ethene monomer then forms a single covalent bond with two other monomers

Question 3

What is the use of poly(ethene)?

Answer 3

They are used to make plastic bags or clingfilm

Question 4

What are the problems of poly(ethene)?

Answer 4

Most plastics are non-biodegradable and cannot be broken down by bacteria in soil.

Question 5

What are the pollution problems caused by disposal of non-biodegradable plastics?

Answer 5

Land: Amt of waste in landfills will accumulate
Water: Will affect marine life and may clog up rivers and drains
Air: Toxic gases and air pollutants are produced when plastics are burnt

Question 6

What is the physical method of recycling plastics?

Answer 6

Small pieces of plastic are melted, cooled, pulled into stands and cut into small pellets.
Pellets can be used to make new products

Question 7

What is the chemical method of recycling plastics?

Answer 7

Can be cracked into shorter chain alkanes and alkenes to be used as fuel and other useful chemicals

Question 8

What are the social, economic and environmental issues of recycling plastic?

Answer 8

Environment: Wastewater generated from recycling process may contaminate water bodies and cause water pollution
Economic: Process for recycling plastics may incur a higher cost than disposal in landfills or incineration. Cost of recycling may exceed value of recycled plastics.
Social: Inconvenience, unaware of proper way to recycle plastics, takes time and effort to make recycling a lifestyle.