Chemistry A-Level
Units and magnitude checks
What Units and magnitude checks means in Chemistry A-Level, as defined for OCR.
Definition of Units and magnitude checks
Check what you remember
Read the wording for your board, then hide it and explain Units and magnitude checks in your own words. Rough notes are fine. This is a self-check, with no mark or grade.
Reference: OCR
The answer is reported in kJ mol⁻¹ with a sensible magnitude and sign consistent with the cycle, keeping units consistent throughout.
Topics that use Units and magnitude checks
- Lattice enthalpy (OCR A-Level)
Related terms
- Born–Haber cycle
- Effect of ionic charge and radius on lattice enthalpy
- Electron affinity
- Enthalpy change of hydration
- Enthalpy change of solution
- Enthalpy of atomisation
- enthalpy of formation
- Enthalpy sign and exothermic formation
Using Units and magnitude checks in the exam
Check the command word and mark scheme for your exact question. After comparing your explanation with the reference, use the term in an answer on the linked topic. This practice does not predict an exam mark.
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