Chemistry A-Level
Sign conventions in thermochemistry
What Sign conventions in thermochemistry means in Chemistry A-Level, as defined for OCR.
Definition of Sign conventions in thermochemistry
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Read the wording for your board, then hide it and explain Sign conventions in thermochemistry in your own words. Rough notes are fine. This is a self-check, with no mark or grade.
Reference: OCR
Each combustion enthalpy keeps its negative sign, and the final ΔrH is reported with the correct sign and units, kJ mol⁻¹.
Topics that use Sign conventions in thermochemistry
- 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 Sign conventions in thermochemistry in the exam
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