2.7 Electrochemistry
Electrolytes, electrolysis, electrodes, molten and aqueous products, half-equations, electroplating, extraction and simple cells.
How to study for CCEA GCSE Chemistry
Connect particle models to observations, balance every quantitative relationship, and prepare each prescribed practical from safe method through analysis and evaluation.
Core concepts
Concept 1
Electrolysis uses direct current to drive redox at electrodes while mobile ions carry charge through the electrolyte.
Exam cue: Identify all mobile ions before predicting electrode products.
Concept 2
Cations are reduced at the cathode and anions are oxidised at the anode; aqueous product prediction also considers water-derived ions.
Exam cue: Balance atoms and charge in each electrode half-equation.
Concept 3
Chemical cells produce a potential difference from a spontaneous redox reaction, unlike electrolysis which consumes electrical energy.
Exam cue: Separate the signs of electrolytic electrodes from the oxidation and reduction definitions.
Risk pitfalls and guardrails
Saying electrons flow through the electrolyte.
Guardrail: Do not import an England board, Single Award or Double Award structure, and do not replace a particle-level explanation with a vague observation.
Assuming the compound's ions are always discharged in an aqueous solution.
Guardrail: Do not import an England board, Single Award or Double Award structure, and do not replace a particle-level explanation with a vague observation.
Reversing anode oxidation and cathode reduction.
Guardrail: Do not import an England board, Single Award or Double Award structure, and do not replace a particle-level explanation with a vague observation.
Memory anchors
Electrolyte
A molten or dissolved ionic substance that conducts through mobile ions.
Cathode
Electrode where reduction occurs.
Anode
Electrode where oxidation occurs.
Reduction half-equation
A species gains electrons with atoms and charge balanced.
Electroplating
Electrolysis depositing a thin metal layer onto an object.
Chemical cell
A system converting chemical energy into electrical energy through redox.
Checkpoint rule
Do the check-up only after you can summarize each concept in one sentence and identify one dangerous pitfall from memory.
Knowledge Check (after reading)
Short check-up to confirm understanding of this module.
Check-up Questions
A molten ionic compound conducts because its ions can move to the electrodes. How should the conducting substance be classified?
Why does solid sodium chloride not electrolyse?
Answer all questions to submit.
Next step personalized recommendations
Continue learning
Move forward only after this module is stable.
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