Alkenes undergo addition reactions — atoms ADD ACROSS the double bond, breaking it and forming two single bonds.
1. Addition of Hydrogen (Hydrogenation)
C₂H₄ + H₂ → C₂H₆
Conditions: Ni catalyst, 150°C
2. Addition of Bromine (Bromination)
C₂H₄ + Br₂ → C₂H₄Br₂
Room temperature, no catalyst needed
3. Addition of Water (Hydration)
C₂H₄ + H₂O → C₂H₅OH
Conditions: Phosphoric acid catalyst, 300°C, 70 atm pressure
This deep dive covers Addition Reactions of Alkenes within Alkenes for GCSE Chemistry. Revise Alkenes in Organic Chemistry for GCSE Chemistry with 20 exam-style questions and 15 flashcards. This is a high-frequency topic, so it is worth revising until the explanation feels precise and repeatable. It is section 6 of 14 in this topic. Use this deep dive to connect the idea to the wider topic before moving on to questions and flashcards.
Practice questions for Alkenes
What is the general formula for alkenes?
Explain what is meant by the term 'unsaturated' when applied to alkenes.