1. 1
   A packaging company manufactures plastic bags from poly(ethene), which is formed by joining together many ethene monomer molecules.

   (a)

   What is the correct term for this type of polymer-forming process?

   [1 mark]

   • ACondensation polymerisation
   • BAddition polymerisation
   • CFermentation
   • DEsterification

   (b)

   Which structural feature of the ethene monomer allows it to undergo this polymerisation reaction?

   [1 mark]

   • AThe presence of an -OH group
   • BThe presence of a -COOH group
   • CThe presence of a carbon-carbon double bond
   • DThe presence of a benzene ring

   (c)

   Describe, in words, the repeat unit of poly(ethene), including how the carbon-carbon double bond of the monomer changes during polymerisation.

   [2 marks]

   Total for question 1: 4 marks

2. 2
   A manufacturer of plumbing pipes uses poly(chloroethene), also known as PVC, which is formed from the monomer chloroethene.

   (a)

   What is the structure of the chloroethene monomer?

   [1 mark]

   • ACH2=CHCl
   • BCH3-CH2Cl
   • CCHCl3
   • DCH2=CH2

   (b)

   When the polymer pipes eventually reach the end of their life, disposal is a concern. Which statement correctly describes a problem with disposing of poly(chloroethene) by burning it?

   [1 mark]

   • ABurning produces only harmless carbon dioxide and water
   • BBurning converts the polymer back into its original monomer safely
   • CBurning causes the polymer to biodegrade rapidly
   • DBurning can produce toxic gases, since the polymer contains chlorine

   (c)

   Describe the repeat unit of poly(chloroethene), and explain why addition polymers such as this one are generally difficult to dispose of safely.

   [2 marks]

   Total for question 2: 4 marks

3. 3
   A textile company produces a biodegradable polyester fabric by reacting a dicarboxylic acid with a diol in a condensation polymerisation reaction.

   (a)

   Explain what is meant by 'condensation polymerisation', and state the small molecule released as a by-product during this process.

   [3 marks]

   (b)

   Explain how the structural formula of the polyester repeat unit could be deduced from the formulae of the dicarboxylic acid and diol monomers used, and state why this particular polyester is described as a biopolyester.

   [4 marks]

   Total for question 3: 7 marks

4. 4
   An environmental campaign group is raising concerns about the amount of addition polymer waste, such as poly(ethene) and poly(chloroethene), accumulating in landfill sites and oceans.

   (a)

   Explain, with reference to the structure of addition polymers, why they cause such persistent environmental problems, and describe the specific risks associated with burning chlorine-containing polymers as a disposal method.

   [6 marks]

   (b)

   Evaluate whether switching from conventional addition polymers to biodegradable polyesters, formed by condensation polymerisation, would meaningfully solve the environmental problems caused by plastic waste, considering both the chemistry of biodegradation and practical challenges of adoption.

   [6 marks]

   Total for question 4: 12 marks

End of questions