Chemistry A-Level
enthalpy of hydrogenation
What enthalpy of hydrogenation means in Chemistry A-Level, as defined for AQA.
Definition of enthalpy of hydrogenation
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Reference: AQA
The energy released when hydrogen is added to a C=C, as when cyclohexene releases 120 kJ mol⁻¹.
Topics that use enthalpy of hydrogenation
- Bonding (A-level only) (AQA A-Level)
Related terms
- bromine water test
- delocalisation
- delocalisation energy
- energy of products
- equal bond lengths
- relative stability
- substitution over addition
- Kekulé model
Using enthalpy of hydrogenation in the exam
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