write working and functioning extraction of aluminium.
Answers
Answer:
Concentration of ore is done by baeyer's process using chemical method.
The electrolytic reduction of alumina is done by hall heroult's process. The reaction at cathode is : 2Al
3+
+6e
−
→2Al Thus pure aluminium metal is formed at the cathode.
Cryolite is sodium aluminium fluoride (Na
3
AlF
6
). It ia an ore of aluminium. Cryolite and fluorspar acts as an solvent.
Al(OH)
3
→Al
2
O
3
+water
The oxygen evolved at the anode escapes as a gas or reacts with the carbon anode. The anode is thus oxidized to carbon monoxide which either burns giving CO
2
or escapes. Thus, anode has to be replaced as it is consumed periodically
Answer:
cryolite is added to the molten mixture of alumina to reduce the melting point .
the formula of cryolite is Na3AlF6.