Cambridge IGCSE·Co-ordinated Sciences 0654·Chemistry
Electrochemistry
Key knowledge — Electrochemistry
Key facts & rules
- Electrolysis: uses electrical energy to decompose an ionic compound (in solution or molten).
- Electrolyte: ionic compound that conducts electricity when dissolved or molten.
- Cathode (−): positive ions (cations) are attracted here and GAIN electrons (reduction).
- Anode (+): negative ions (anions) are attracted here and LOSE electrons (oxidation).
- Electrolysis of brine (NaCl solution): cathode → hydrogen gas; anode → chlorine gas; NaOH remains.
- Electrolysis of dilute H₂SO₄: cathode → hydrogen gas; anode → oxygen gas.
- Electroplating: object to be plated = cathode; plating metal = anode; solution of plating metal ions = electrolyte.
- Extraction of aluminium: Al₂O₃ dissolved in molten cryolite; cathode → Al; anode → O₂.
IGCSE Chemistry — Electrochemistry
1640 Cambridge IGCSE 0654 chemistry past paper questions on electrochemistry, organised by subtopic. Pick a subtopic to start practising.
About electrochemistry on IGCSE 0654
Electrolysis of molten and aqueous substances, the products at each electrode, and electroplating, plus simple cells.