c6.1.8 extracting aluminium

Question 1

what ore is aluminium found in

Answer 1

bauxite

Question 2

why can’t aluminium be extracted using normal electrolysis

Answer 2

aluminium oxide doesn’t dissolve in water and has a melting point of 2000 degrees

Question 3

what must you do to the aluminium oxide to extract the aluminium

Answer 3

dissolve it in molten cryolite

allows electrolysis to happen at 950 degrees

Question 4

what is the anode now

Answer 4

carbon anodes

Question 5

what is the cathode now

Answer 5

they are the carbon lining of the cell

Question 6

what is produced at the anode

Answer 6

oxygen

Question 7

what is produced at the cathode

Answer 7

aluminium

Question 8

more specifically, what are the electrodes made out of

Answer 8

graphite

Question 9

half equation for what happens at the cathode

Answer 9

Al(3+) +3e- = Al

Question 10

half equation for what happens at the anode

Answer 10

2O(2-) = O2 + 4e-

Question 11

full equation for extracting aluminium

Answer 11

2Al2O3 (l) = 4Al (l) + 3O2 (g)

Question 12

why must the anodes be replaced every couple of weeks

Answer 12

the carbon and oxygen react to form carbon dioxide