the extraction of aluminium

?
  • Created by: Abi14
  • Created on: 14-04-14 10:34
how is aluminium extracted?
aluminum is more reactive than carbon and so it must be extracted from its ore by electrolysis. its ore contains aluminium oxide whihc must be purified and then melted so that it can be electrolysed. Aluminium oxide melts at over 2000'c, which would
1 of 8
how is aluminium extracted? (continued)
need a lot of energy. aluminium oxide is mixed with another ionic compound called cryolite, so that the mixture melts at about 850'c. the mixture can be electrolysed at this lower temperature and produces aluminium and oxygen as products.
2 of 8
what is the overall reaction the electrolysis cell? (the extraction of aluminium)
aluminium oside ---> aluminium + oxygen
3 of 8
what happens to the cryolite when the reaction has taken place?(the extraction of aluminium)
it remains in the cell and the fresh aluminium oxide is added as aluminum and oxygen are priduced.
4 of 8
what happens at the negative electrode? (the extraction of aluminium)
aluiminium ions are reduced to aluminum atoms by gaining ecetrons. the molten aluminium metal is collected from the bottom of the cell.
5 of 8
what happens at the postive electrode? (the extraction of aluminium)
ions are oxidised to oxygen atoms by losing electrons and the oxygen atoms form oxygen molecules.
6 of 8
what are the half equation of the extraction of aluminium?
.
7 of 8
what are the positive electrodes used in the cell made from? (the extraction of aluminium)
carbon. at high temperature of the cell the oxygen reacts with the carbon electrodes to produce crbon dioxide. this means that the carbon electrodes gradually burn away and so they have to be replaced regularly.
8 of 8

Other cards in this set

Card 2

Front

how is aluminium extracted? (continued)

Back

need a lot of energy. aluminium oxide is mixed with another ionic compound called cryolite, so that the mixture melts at about 850'c. the mixture can be electrolysed at this lower temperature and produces aluminium and oxygen as products.

Card 3

Front

what is the overall reaction the electrolysis cell? (the extraction of aluminium)

Back

Preview of the front of card 3

Card 4

Front

what happens to the cryolite when the reaction has taken place?(the extraction of aluminium)

Back

Preview of the front of card 4

Card 5

Front

what happens at the negative electrode? (the extraction of aluminium)

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Chemistry resources:

See all Chemistry resources »See all Electrolysis resources »