FreeScienceLessons · AQA ChemistryAlkenes and Polymers
Cognito · AQA ChemistryCracking and the production of alkenes
Key facts
Alkenes — fill in the table
Term
Detail
Alkenes
Ethene
Propene
Butene
Test for alkene
Addition reaction
Hydration of ethene
Polymerisation — fill in the table
Term
Detail
Addition polymerisation
Poly(ethene) equation
Repeat unit
Condensation polymerisation
Nylon (polyamide)
Polyester
Exam questions — 4 questions · 10 marks
⚡ Extended questions included. Read the hint. Show all working. AI marks against the real AQA mark scheme.
1 markAlkene testAQA 8462 P2 style
How can you distinguish between an alkane and an alkene using a simple chemical test?
A Add universal indicator — alkenes turn it red
B Add bromine water — alkenes decolourise it from orange to colourless; alkanes have no effect
C Burn both — alkenes produce a smoky flame; alkanes burn cleanly
D Add sodium hydroxide — alkenes react but alkanes do not
1 markAddition polymerisationAQA 8462 P2 style
Which type of monomer is required for addition polymerisation?
A A molecule with two carboxylic acid groups
B A molecule with two amine groups
C An unsaturated molecule with a carbon–carbon double bond
D Any molecule that can dissolve in a monomer solution
4 marksCompare addition and condensation polymerisationAQA 8462 P2 style
Compare addition polymerisation and condensation polymerisation. Give the type of monomer needed for each, what bonds form, and whether any small molecule is released. (4 marks)
Hint: Two clear contrasts: monomer type, bond formed, whether small molecule released. Cover both types with examples.
+40 XP
3 marksBromine water testAQA 8462 P2 style
A student has two unlabelled liquids — one is hexane and one is hexene. Describe a test to identify which is which and explain the chemistry. (3 marks)