Chemistry A-Level
Enthalpy change (∆H)
What Enthalpy change (∆H) means in Chemistry A-Level, as defined for OCR.
Definition of Enthalpy change (∆H)
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Reference: OCR
A measure of the heat energy exchanged with the surroundings at constant pressure, recorded with a sign fixed relative to the system.
Topics that use Enthalpy change (∆H)
- Enthalpy changes (OCR A-Level)
Related terms
- ∆H of combustion
- ∆H of formation
- Activation energy
- Approximate estimate
- Average bond enthalpy
- Averaging over gaseous compounds
- Bond breaking and bond making
- Bond enthalpy
Using Enthalpy change (∆H) in the exam
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