Chemistry A-Level
Enthalpy of formation and combustion cycles
What Enthalpy of formation and combustion cycles means in Chemistry A-Level, as defined for OCR.
Definition of Enthalpy of formation and combustion cycles
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Reference: OCR
If formation enthalpies are given for the reactants and products of an unfamiliar reaction, the reaction enthalpy equals the sum of the products' formation enthalpies minus the sum of the reactants'.
Topics that use Enthalpy of formation and combustion cycles
- 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 of formation and combustion cycles in the exam
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