Reactions of Alkenes
Use this landing page to move quickly between the main alkene reaction revision pages for Topic 5. Each card links to a focused page covering addition reactions of alkenes and the chemical tests or conditions students need to recognise.
Choose a Reactions of Alkenes Page
Alkenes react because the C=C double bond contains an exposed pi bond with high electron density. These pages separate the key alkene reactions so that students can revise the reagent, conditions, observations and products for each pathway.
Key idea: Most alkene reactions are addition reactions. The C=C double bond opens and new atoms or groups add across the two carbon atoms.
Halogens
Revise addition of halogens to alkenes and how dihalogenoalkanes form across the carbon-carbon double bond.
Hydrogen Halide
Learn how hydrogen halides add to alkenes to form halogenoalkanes, including the importance of the C=C bond.
Bromine Water
Revise the chemical test for alkenes, including the colour change when bromine water reacts with a C=C bond.
Hydrogen
Learn how hydrogenation converts alkenes into alkanes by adding hydrogen across the double bond.
Steam
Revise hydration of alkenes and how steam is used to produce alcohols under suitable conditions.
KMnO₄
Review oxidation of alkenes with potassium manganate(VII), including the key reagent and expected test observations.
How to Use These Pages
Start with the halogen and hydrogen halide pages to secure the idea of electrophilic addition across the C=C bond. Then use bromine water as the diagnostic test for unsaturation. Finally, move to hydrogenation, hydration with steam and oxidation using KMnO₄ to compare how different reagents change the functional group.
Exam focus: For each reaction, learn the reagent, conditions, product type and any visible observation. Then link the reaction back to the electron-rich C=C double bond.
Copyright notice: This revision page, including its written explanations, layout and teaching sequence, is produced for Online Learning System by Dr. Mohammed Al-Fatah. It is intended for student revision and may not be copied, redistributed or republished without permission.