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Edexcel A Level Chemistry

Alkenes

Alkenes are unsaturated hydrocarbons containing a carbon-carbon double bond. These pages separate the topic into bonding, isomerism, electrophilic addition, reactions and polymer chemistry so that students can revise the structure and reactivity of alkenes clearly.

Exam Papers
Paper 2
9CH0/02
Specification Points
6.5 – 6.29
12 points covered
Sub-topics
6 lessons
Revision notes available
Exam Board
Edexcel
Pearson 9CH0

Revision Notes

6 revision notes, in the order the specification teaches them.

Orbital picture of a carbon-carbon double bond, with a sigma bond between the atoms and a pi bond above and below
1

Alkene Bonding

Revise the carbon-carbon double bond, including sigma and pi bonding, restricted rotation and the unsaturated nature of alkenes.

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Two arrangements around a locked double bond that cannot rotate
2

Geometric Isomerism

Learn how restricted rotation around the C=C bond can produce E and Z stereoisomers when each carbon has two different groups.

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A positive particle attracted towards the electron-rich double bond
3

Electrophilic Addition Mechanism

Revise how electrophiles attack the electron-rich pi bond and how curly arrows show the formation of carbocation intermediates.

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A double bond linked to the reagents it reacts with
4

Reactions of Alkenes

Review the main addition reactions of alkenes, including reactions with hydrogen, steam, halogens and hydrogen halides.

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Small units joining into one long polymer chain
5

Polymerisation Reactions

Learn how alkene monomers join together by addition polymerisation to form long-chain polymers with repeating units.

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Plastic buried in the ground and an incinerator with a chimney filter
6

Polymer Waste

Revise the environmental problems caused by polymer waste and compare disposal, recycling and biodegradability issues.

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Summary Map

Download, print and revise the reactions of this topic at a glance.

Summary map

Download, print and revise the reactions of this topic at a glance.

Illustration of a summary map: compounds joined by reaction arrows
Summary map · PDF

Alkenes Map

Edexcel A Level Chemistry · Topic 6C Alkenes

Every reaction on one A4 page: reagents, conditions and reaction type for each arrow, colour coded, with the key tests.

Download the map6 reactions · A4 portrait · print ready

© 2026 Online Learning System. For personal study: printing is allowed; editing, copying and redistribution are not.

Virtual Lessons

Recorded video lessons that teach the topic step by step.

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Virtual Lessons

Taught step by step in 4 recorded video lessons, to watch at your own pace.

Topic 6C Alkenes taught by a specialist chemistry teacher, in 4 recorded video lessons that follow the specification.

  • Learn it before you revise itEach lesson explains the chemistry step by step, with the diagrams, mechanisms and worked examples the exam expects.
  • At your own pacePause, rewind and rewatch any part. Each lesson opens where you stopped.
  • Your progress is keptA lesson is ticked off once you have watched most of it, here and in your course on Moodle.

MCQ Bank

Multiple-choice papers on this topic, marked the moment you submit. MCQ (A) is free.

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Test yourself: 5 MCQ papers

Exam-style multiple-choice papers, marked the moment you submit with every answer explained. MCQ (A) is free.

5 exam-style multiple-choice papers, MCQ (A) to (E): 90 questions on Topic 6C Alkenes, written the way the exam asks them.

  • Marked the moment you submitYour score straight away, with every answer explained, right or wrong.
  • Revise what you missedEach explanation links to the revision notes for that point.
  • MCQ (A) is freeTry the first paper now. MCQ (B) to (E) come with the course.
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SAQ Bank

Written, drawn and worked exam practice on this topic, marked by a specialist chemistry teacher.

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Written and drawn answers: 12 papers

Draw, write and calculate the way the exam asks, then a specialist chemistry teacher marks your work.

12 exam papers, (A) to (L): 170 questions on Topic 6C Alkenes with no multiple choice. You write explanations, work out calculations and draw answers: structures, mechanisms and diagrams.

  • Answer the way the exam asksThe real paper wants written, worked and drawn answers, so that is how you practise.
  • Marked by a teacher, assisted by KASPA specialist chemistry teacher marks every answer against the mark scheme, with feedback on what to fix.
  • One paper marked each weekYour marked paper comes back here with every marking point shown.
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Revision Game

Match reagents to products, free, with your board's reagents and conditions.

Illustration of memory game cards, two turned face up as a matching pairFree

Revision Game: Alkenes

Turn the cards over two at a time: match reagents to what they make, and find how each product is made.

A free memory game on the reactions in this topic, with your board's reagents, conditions and spec points.

  • Two ways to playMatch each set of reagents to what the reaction makes, or see a product and find the reactant and reagents that make it.
  • Drawn the way the exam draws themEvery structure is drawn in ChemDraw, with the reagents and conditions your exam board asks for.
  • It countsRounds earn XP and keep your streak going, and every correct match shows in your KASP analytics, apart from your marks.

Study Cards

Pick a deck, then turn each card to check what you remember.

Specification

Every specification point in this topic, in the exam board's own words. Rate how confident you are with each one.

Official Pearson Edexcel documentsSpecification (opens the Pearson Edexcel website in a new tab)Data booklet (opens the Pearson Edexcel website in a new tab)

Self-assessment · 32 points

Sign in to rate how confident you feel about each point. Your ratings are saved to your account, follow you to any device, and appear beside your KASP analytics, kept apart from your marks.

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6

  1. C.18

    know the general formula for alkenes

    Revise
  2. C.19

    know that alkenes and cycloalkenes are unsaturated hydrocarbons

    Revise
  3. C.19 a

    know that alkenes are unsaturated hydrocarbons

    Revise
  4. C.19 b

    know that cycloalkenes are unsaturated hydrocarbons

  5. C.20 a

    understand bonding in alkenes in terms of sigma bonds

    Revise
  6. C.20 b

    understand bonding in alkenes in terms of pi bonds

    Revise
  7. C.21

    know what is meant by the term ‘electrophile’

    Revise
  8. C.22i

    understand the addition reactions of alkenes with: hydrogen, in the presence of a nickel catalyst, to form an alkane Knowledge of the application of this reaction to the manufacture of margarine by catalytic hydrogenation of unsaturated vegetable oils is expected.

    Revise
  9. C.22ii

    understand the addition reactions of alkenes with: halogens to produce dihalogenoalkanes

    Revise
  10. C.22iii

    understand the addition reactions of alkenes with: hydrogen halides to produce halogenoalkanes

    Revise
  11. C.22iv

    understand the addition reactions of alkenes with: steam, in the presence of an acid catalyst, to produce alcohols

    Revise
  12. C.22v

    understand the addition reactions of alkenes with: potassium manganate(VII), in acid conditions, to oxidise the double bond and produce a diol

    Revise
  13. C.23

    understand that heterolytic bond fission of a covalent bond results in the formation of ions

    Revise
  14. C.24i

    understand the mechanism of the electrophilic addition reactions between alkenes and: halogens

    Revise
  15. C.24ii

    understand the mechanism of the electrophilic addition reactions between alkenes and: hydrogen halides, including addition to unsymmetrical alkenes

    Revise
  16. C.24iii

    understand the mechanism of the electrophilic addition reactions between alkenes and: other given binary compounds Use of the curly arrow notation is expected − curly arrows should start from either a bond or from a lone pair of electrons. Knowledge of the relative stability of primary, secondary and tertiary carbocation intermediates is expected.

    Revise
  17. C.24iii a

    use curly arrow notation in electrophilic addition mechanisms

    Revise
  18. C.24iii b

    know the relative stability of primary secondary and tertiary carbocation intermediates

    Revise
  19. C.24iii c

    understand the mechanism of electrophilic addition with other given binary compounds

    Revise
  20. C.25

    know the qualitative test for a C=C double bond using bromine or bromine water

    Revise
  21. C.25 a

    know the qualitative test for a C=C double bond using bromine

    Revise
  22. C.25 b

    know the qualitative test for a C=C double bond using bromine water

    Revise
  23. C.26 a

    know that alkenes form polymers through addition polymerisation

    Revise
  24. C.26 b

    be able to identify the repeat unit of an addition polymer from the monomer

    Revise
  25. C.26 c

    be able to identify the monomer from the repeat unit of an addition polymer

    Revise
  26. C.27i

    know that waste polymers can be separated into specific types of polymer for: recycling

    Revise
  27. C.27ii

    know that waste polymers can be separated into specific types of polymer for: incineration to release energy

    Revise
  28. C.27iii

    know that waste polymers can be separated into specific types of polymer for: use as a feedstock for cracking

    Revise
  29. C.28 a

    understand that chemists can contribute to more sustainable use of materials in terms of energy use over the life cycle of polymer products

    Revise
  30. C.28 b

    understand that chemists can contribute to more sustainable use of materials in terms of resource use over the life cycle of polymer products

    Revise
  31. C.29i

    understand how chemists limit the problems caused by polymer disposal by: developing biodegradable polymers

    Revise
  32. C.29ii

    understand how chemists limit the problems caused by polymer disposal by: removing toxic waste gases caused by incineration of plastics

    Revise