Chemistry A-Level
Hess's law and route independence
What Hess's law and route independence means in Chemistry A-Level, as defined for OCR.
Definition of Hess's law and route independence
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Read the wording for your board, then hide it and explain Hess's law and route independence in your own words. Rough notes are fine. This is a self-check, with no mark or grade.
Reference: OCR
The total enthalpy change is independent of route, so the sum of the steps one way equals the sum of the steps the other way.
Topics that use Hess's law and route independence
- 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's law and route independence in the exam
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