Chemistry A-Level
Hess cycle
What Hess cycle means in Chemistry A-Level, as defined for OCR.
Definition of Hess cycle
Check what you remember
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Reference: OCR
A route that starts from the reactants and products of the reaction and takes both down to the same combustion products, such as CO₂(g) and H₂O(l).
Topics that use Hess cycle
- 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 Hess cycle in the exam
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