⚡ Show all working — the AI marks against the AQA mark scheme. Method marks awarded for correct working even if the final answer is wrong.
1 markAlkene testAQA 8462
What is the test for an alkene and what is observed?
A Add acidified KMnO4 — turns colourless
B Add bromine water — decolourises from orange to colourless
C Add universal indicator — turns green
D Burns with no soot
3 marksAddition reactionsAQA 8462
Ethene reacts with steam to form ethanol. (a) Write the word equation. (b) What type of reaction is this? (c) Why does this reaction have 100% atom economy? (3 marks)
+30 XP
1 markPolymer requirementAQA 8462
Why can alkanes NOT undergo addition polymerisation?
A Alkanes are too large
B Alkanes are gases
C Alkanes have no C=C double bond — no site for addition reactions
D Alkane monomers repel each other
3 marksCompare alkane and alkeneAQA 8462
Compare alkanes and alkenes: (a) general formula, (b) bonding, (c) reaction with bromine water. (3 marks)