combining half-equations
What combining half-equations means in Chemistry A-Level, as defined for AQA.
Definitions of combining half-equations
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Reference: AQA
Scale the two half-equations so the electrons cancel and then add them, never multiplying E⦵ by that scaling factor.
Scaling the half-equations so the electrons cancel exactly before adding them together into the overall equation.
Scale each so the electrons cancel, then add and cancel anything appearing on both sides.
Topics that use combining half-equations
- Electrode potentials and cells (A-level only) (AQA A-Level)
- Oxidation, reduction and redox equations (AQA A-Level)
- Variable oxidation states (A-level only) (AQA A-Level)
Related terms
- 4s and 3d energies
- cell diagrams
- charge balance
- deducing oxidation states
- Disproportionation
- effect of concentration
- feasibility
- feasibility prediction
Using combining half-equations in the exam
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