electroylisis

Question 1

al2o3 mixed with cryolite

Answer 1

to lower melting point

Question 2

half equation at negative electrode

aluminium oxide electrolysis

Answer 2

Al3+ + 3e- —> Al

Question 3

half equation at positive electrode

aluminium oxide electrolysis

Answer 3

2O2- —> O2 + 4e-

Question 4

al2o3 electrolysis

at the positive electrode

Answer 4

O2- ions are negative
form oxygen gas
graphite react with oxygen producing co2
electrode replaced regularly

Question 5

al2o3 electrolysis

negative electrode

Answer 5

al3+ ions attracted to al atoms
liquid al runs to bottom of cell and tapped off

layer of graphite around inside of cell forms negative electrode
post tube electrodes also made from graphite

Question 6

electrolysis

Answer 6

breaking down of a compound using electrical energy

Question 7

electrolyte

Answer 7

ionically bonded compounds which carry charge when dissolved in water (aq) or heated (molten liquids)

Question 8

anode

Answer 8

positive

Question 9

cathode

Answer 9

negative

Question 10

electrolysis of lead bromide

Answer 10

anode
2Br- —> Br2 + 2e-

cathode
Pb2+ + 2e- —> Pb