Question: Which of the following metals cannot be extracted by the carbon reduction process?...

Question

Which of the following metals cannot be extracted by the carbon reduction process?

Answer 1

Solution

Aluminium is extracted by electrolytic reduction of mixture of molten Al2O3 + Na3AlF6 + CaF2 .

Due to very high energy of dissociation of Al2O3 , the reduction at such high temperature will give carbide in place of metallic Al according to the following reaction. 2Al2O3 + 6C $\overset{\quad\Delta\quad}{\rightarrow}$ Al4C3 + 3CO2 .