Chemistry A-Level
Enthalpy change of hydrogenation
What Enthalpy change of hydrogenation means in Chemistry A-Level, as defined for OCR.
Definition of Enthalpy change of hydrogenation
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Reference: OCR
The value for benzene is less exothermic than the value predicted for a hypothetical cyclohexatriene with three isolated double bonds, so benzene is more stable than the Kekulé structure implies.
Topics that use Enthalpy change of hydrogenation
- Aromatic compounds (OCR A-Level)
Related terms
- Activating and 2,4-directing effect of the –OH group
- Bond lengths in benzene
- Carbon–carbon bond formation in synthesis
- Comparison with carboxylic acids and the carbonate test
- Delocalised π system and electron density
- Delocalised π system in benzene
- Directing effects
- Directing effects of OH, NH₂ and NO₂
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