Question

Tell me the equations of:
Bayer's Process
Hall Herault's Reduction
Hoope's Refining

PLEASE HELP

Answer 1

baeyers process.......
Al2O3.2H2O=NaAlO2+H2O
NaAlO2 +H2O=Al(OH)3+NaOH
Al(OH)3======Al2O3+H2O
.....
Hall heraults process.......
its is an electrolysis in which alumina is reduced.....
elctrolytes are=20%Al2O3 60%CaF2 & 20%Na3AlF6
Al2O3=(Al3+)+(O2-)
CaF2=(Ca 2+)+(F-)
NaAlF6=(Na+)+(Al 3+)+(F-)

while reduction of alumina...
At cathode ......4(Al3+)+12e=4Al
At anode.......(3O 2-)-6e=3O
3O+3O=3O2
2C+O2=2CO
2CO+O2=2CO2
Hoopes process
while purification of aluminium through electrolysis
at cathode=(Al3+)+3e=Al
at anode=Al-3e=Al3+......

Answer 2

The Hall–Héroult process is the major industrial process for smelting aluminium. It involves dissolving aluminium oxide (alumina) obtained most often from bauxite.
Cathode:

Al+3 + 3 e− → Al
Anode:

O−2 + C → CO + 2 e−
Overall:

Al2O3 + 3 C → 2 Al + 3 CO
In reality much more CO2 is formed at the anode than CO:

Al2O3 + 3/2 C → 2 Al + 3/2 CO2