A structured syllabus summary covering the main ideas commonly required across AQA, OCR A, Edexcel, and WJEC A-level Chemistry specifications.
Overview
The redox and electrode potentials topic usually includes oxidation and reduction as electron transfer, oxidation numbers,
half-equations, full redox equations, standard electrode potentials, the standard hydrogen electrode, electrochemical cells,
cell diagrams, EMF calculations, and the use of E° values to predict reaction feasibility.
Typical Syllabus Content
1. Redox basics
Oxidation = loss of electrons
Reduction = gain of electrons
Oxidising agents accept electrons
Reducing agents donate electrons
2. Oxidation numbers
Assign oxidation states in ions and compounds
Use oxidation numbers to identify redox change
Recognise disproportionation in some specifications
3. Half-equations
Write oxidation half-equations
Write reduction half-equations
Combine them into full redox equations
4. Standard electrode potentials
Define standard electrode potential, E°
Know standard conditions: 298 K, 100 kPa, 1.00 mol dm-3
Measure relative to the standard hydrogen electrode
5. Electrochemical cells
Construct half-cells
Use conventional cell diagrams
Measure cell EMF / cell potential
6. Using E° values
Calculate E°cell from two half-cells
Predict direction and feasibility of redox reactions
Understand limits due to kinetics and non-standard conditions
Board-Specific Emphasis
AQA
Redox definitions and oxidation states
IUPAC half-equation convention
Electrochemical series and E° values
EMF calculations and conventional cell representation
Lithium cells and hydrogen–oxygen fuel cells
OCR A
Redox equations using half-equations and oxidation numbers