Extracting Aluminium Flashcards
1
Q
Why does aluminium need to electrolysed to extract it from its ore
A
As it is more reactive then carbon
2
Q
What is the main ore of aluminium
A
Bauxite
3
Q
What is left once bauxite is purified
A
Al2O3 aluminium oxide
4
Q
Why is aluminium oxide dissolved in cryolite
A
- lowers the melting point to around 900c
- this makes it much cheaper
5
Q
What are the electrodes made of
A
Graphite
6
Q
What occurs at the cathode
A
Aluminium is formed
7
Q
What occurs at the anode
A
Oxygen is formed
8
Q
Why is CO2 also produced
A
As the oxygen atoms react with the graphite electrode (carbon)
9
Q
Why does the anode need to be replaced frequently
A
It is constantly getting worn down due to reacting with the oxygen
