Chemistry A-Level
Approximate estimate
What Approximate estimate means in Chemistry A-Level, as defined for OCR.
Definition of Approximate estimate
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Reference: OCR
The result is approximate because the actual bonds in the reacting molecules differ from the averaged values, and because the calculation assumes all species are gaseous.
Topics that use Approximate estimate
- Enthalpy changes (OCR A-Level)
Related terms
- ∆H of combustion
- ∆H of formation
- Activation energy
- Average bond enthalpy
- Averaging over gaseous compounds
- Bond breaking and bond making
- Bond enthalpy
- Calculating enthalpy changes
Using Approximate estimate in the exam
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