electrolysis of aluminium oxide

Question 1

electrolysis can be used to extract metals more reactive then ___ from their compound?

Answer 1

electrolysis can be used to extract metals more reactive then carbon from their compound

Question 2

why is electrolysis expensive?

Answer 2

large amount of money is required to produce electrical current

Question 3

what 2 ions make up aluminium oxide?

Answer 3

Al3+ and O2-

Question 4

what is aluminium oxide mixed with and why?

Answer 4

aluminium oxide is mixed with cryolite which lowers boiling point
reduces amount of energy needed and saves money

Question 5

what is the half equation between aluminium and the negative cathode, what type of reaction is this?

Answer 5

Al3+ 3e- -> Al
reduction

Question 6

what is the half equation between oxygen and the positive anode, what type of reaction is this?

Answer 6

2 O2- -4e- -> o2
oxidation

Question 7

why must anode be replaced regularly?

Answer 7

anode is made of carbon, which reacts with oxygen to form carbon dioxide