Question

What chemcial principal is involved in choosing a reducing agent for getting the metal from its oxide ore? Consider the metal oxides `Al_(2)O_(3) and Fe_(2)O_(3)` and justify and choice of reducing agent in each case.

Answer 1

(i) Thermodynamci factor helps us in choosing a suitable reducing agent for the reducing agent for the reducation of a particular metal oxide to the metallic state
(ii) Any metal will reduce the oxides of other metals which lie aboe it in the Ellingham diagram because the standard free energy change `(Delta_(r)G^(@))` of the combined redox reaction will be-ve by an amount equal to the differenc in `Delta_(f)G^(@)` fo two metal oxides.
Thus, both Al and Zn can reduces `Fe_(2)O_(3)` to Fe but Fe but Fe cannot reduce `Al_(2)O_(3)` to Al.