Addition polymerisation

4 marks · Normal

Addition polymers such as poly(chloroethene) are made from small molecules called monomers.

(a)

Name the type of reaction used to make poly(chloroethene).

[1 mark]

(b)

Describe the role of an initiator in the preparation of addition polymers.

[1 mark]

(c)

Draw the structure of chloroethene, the monomer used to make poly(chloroethene).

[1 mark]

(d)

State one use of poly(chloroethene).

[1 mark]

Work this out on paper, then compare with the answer and worked solution below. With a free account you can submit written answers for marking.

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(a) Addition polymerisation · must show Identifies 'addition polymerisation'

(b) The initiator starts the reaction/opens the double bond so monomers can join together. It is used up in the reaction. · must show Mentions initiator starts the process/reaction or opens the double bond, Not called a catalyst

(c) Displayed structure of chloroethene (H2C=CHCl) · must show Structure must show C=C, with one H and one Cl on second carbon, two H on first

(d) E.g. used to make pipes, cable insulation, or window frames. · must show Valid use of poly(chloroethene)

Also accept: Polyvinyl chloride for poly(chloroethene); Accept wire insulation, pipes, etc.

Common mistakes: Calling the reaction 'condensation polymerisation'; Calling the initiator a 'catalyst'

Show mark scheme and worked solution

Marking points

B1 (a) · 1 mark · Identifies addition polymerisation

B2 (b) · 1 mark · Describes that the initiator starts the process or opens the double bond

B3 (c) · 1 mark · Draws correct structure for chloroethene

B4 (d) · 1 mark · States a valid use of poly(chloroethene)

Worked solution

a) Addition polymerisation

b) An initiator starts the reaction by opening the double bond in the monomer, allowing them to join into a chain. It is used up in the reaction.

c) Chloroethene structure (displayed structure as above).

d) Used to make pipes, window frames, or insulation for wires.