Chemistry A-Level
substitution over addition
What substitution over addition means in Chemistry A-Level, as defined for AQA.
Definition of substitution over addition
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Reference: AQA
A substitution replaces a hydrogen atom so the delocalised ring is regenerated and the stability is kept, whereas addition would break the ring and lose that stability.
Topics that use substitution over addition
- Bonding (A-level only) (AQA A-Level)
Related terms
- bromine water test
- delocalisation
- delocalisation energy
- energy of products
- equal bond lengths
- relative stability
- enthalpy of hydrogenation
- Kekulé model
Using substitution over addition in the exam
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