CAIE IGCSE Chemistry 9.6.5 Aluminium extraction from purified
Practise aluminium extraction by electrolysis, including cryolite, carbon anodes, electrode products and ionic half-equations.
- Syllabus
- 2026–2028
- Course
- Chemistry 0620
Practise aluminium extraction by electrolysis, including cryolite, carbon anodes, electrode products and ionic half-equations.
Aluminium is extracted from aluminium oxide by electrolysis.
Aluminium can be extracted by electrolysis using the apparatus shown.

Give two reasons why cryolite is used.
1
2
any 2 from:
- increases conductivity
- as a solvent
- lowers the operating temperature
Write the ionic half-equation for the formation of aluminium during the electrolysis.
Al3++3e−→Al
Explain how carbon dioxide gas is formed at the anodes.
oxygen is made at the anode
the anodes are made of carbon
oxygen (made) reacts with carbon