Chemistry A-Level
initiation
What initiation means in Chemistry A-Level, as defined for AQA, OCR.
Definitions of initiation
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Check what you remember
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Reference: OCR
The step in which the halogen molecule splits homolytically to form two halogen radicals.
A step that makes radicals from a non-radical and needs ultraviolet light.
Topics that use initiation
- Reaction mechanisms (AQA A-Level)
- Alkanes (OCR A-Level)
Related terms
- propagation
- termination
- Bond angle of about 109.5°
- Consequences for alkane reactivity
- Curly arrow conventions
- Distinguishing σ-bonds from π-bonds
- Effect of branching on boiling point
- Effect of carbon-chain length on boiling point
Using initiation in the exam
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