1. Radical Reactions

2. Starter – 6 minutes
What is the difference between homolytic and heterolytic fission? (5 marks)

3. GCSE recap
What happens when we add bromine water to an alkane? What does this tell us?

4. Reactions of alkanes and Halogens
The reaction has 3 stages
It is a substitution reaction
It is also a chain reaction (we’ll see why in a bit!)

5. Stage 1 - Initiation
This reaction needs some energy to start it off and this energy is supplied by sunlight (uv frequencies).
Eg Br-Br uv 2Br•
What is being formed? What type of fission is this?
This process is sometimes called photodissociation. Why?

6. Stage 2 - Propogation Br• + CH4 HBr + •CH3 •CH3 + Br2 CH3Br + Br•
Why is this a chain reaction?
This stage can happen thousands of times before……….

7. Stage 3 = Termination When radicals meet they form a stable product.
Write as many termination reactions as you can for this series of reactions