36. Aluminium is extracted from alumina (Al2O3
) by electrolysis of a molten mixture of :
(1) Al2O3
 + KF + Na3AlF6
(2) Al2O3
 + HF + NaAlF4
(3) Al2O3
 + CaF2
 + NaAlF4
(4) Al2O3
 + Na3AlF6
 + CaF2

1 Answer

Answer :

Al2O3
 + Na3AlF6
 + CaF2

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