C6 - Electrolysis Flashcards
C6 - Explain what is produced at the positive electrode
The positive electrode is called the anode.
It attracts negatively charged ions called anions.
Atoms in groups 5, 6 and 7
Ions lose electrons to become atoms.
This is called oxidation.
If the negative ion is not a halide (group 7) oxygen is produced
C6 - Explain what is produced at the negative electrode
The negative electrode is called the cathode.
It attracts positively charged ions called cations.
Atoms in groups 1, 2 and 3.
Ions gain electrons to become atoms again.
This is called reduction.
Hydrogen produced if metal is more reactive than hydrogen.
C6 - Describe the process of aluminium extraction.
Aluminium ore is called bauxite.
It is extracted using electrolysis.
Aluminium must be made molten so that electricity can pass through it.
Aluminium metal forms at the cathode - it sinks to the bottom of the tank to be collected.
Oxygen forms at the anode - it reacts with the carbon in the graphite to form carbon dioxide.
The anode is worn away and constantly needs to be replaced.
