extraction of aluminium Flashcards
1
Q
what is the mineral containing aluminium
A
bauxite
2
Q
how do you get bauxite
A
from cast mining
3
Q
why do they add cryalite to molten bauxite
A
lower the melting point to 859
4
Q
what happens during electrolysis
A
the aluminium is reduced at the negative electrode and gains 3 electrons and oxygen is oxidised at the positive electrode and loses 2 electrons
5
Q
what happens with the O2 that is released
A
reacts with the carbon electrode and burns it
6
Q
what is the half equation for oxygen being oxidised
A
2O^2- –> O2 + 4e
7
Q
what is the half equation for aluminium being reduced
A
al^3+ + 3e –> Al
