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

Options

A. Zn
B. Fe
C. Al
D. Sn

Answer

C

Explanation

Aluminium is extracted by electrolytic reduction of mixture of molten `Al_(2)O_(3) + Na_(3)AlF_(6) + CaF_(2)`
Due to very high energy of dissociation of `Al_(2)O_(3)`, the reduction at such high temperature will give carbide in place of metallic Al according to the following reaction `Al_(2)O_(3) + C overset(Delta)rarr Al_(4)C_(3) + CO_(2)`