Half-equations
What Half-equations means in Chemistry A-Level, as defined for AQA, OCR.
Definitions of Half-equations
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Reference: OCR
Separate oxidation and reduction equations in which atoms other than O and H are balanced first, then O with H₂O, H with H⁺ in acidic conditions, and charge with electrons.
Electrons appear on the product side for an oxidation half-equation and on the reactant side for a reduction half-equation.
A redox half-equation is balanced for atoms and charge by adding electrons to the appropriate side.
Separate a redox reaction into the electron loss and the electron gain, built in a fixed order.
Topics that use Half-equations
- Oxidation, reduction and redox equations (AQA A-Level)
- Redox (OCR A-Level)
- Redox and electrode potentials (OCR A-Level)
Related terms
- Oxidising Agent
- Disproportionation
- Electron transfer
- Oxidation
- Oxidation numbers
- Oxidising and reducing agents
- Reducing agent
- Reduction
Using Half-equations in the exam
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