Question

The electrolytic reduction process is used for the extraction of:
A.Highly electropositive metals
B.Metalloids
C.Less reactive metals
D.Transition metals

Answer 1

Hint: There are many methods that are used for extracting the metals from their ores which include reduction of metals, oxides with carbon reduction or electrolytic reduction of the molten metal chlorides, oxides and hydroxides. Methods used for a metal depend on its physical and chemical properties.

Complete step by step answer:
The type of extraction method to be used for the extraction of the metals from their ores depends upon its position in the reactivity series. Metals that lie below the carbon in the reactivity series can be extracted from their respective oxides by heating them with carbon. In this reaction, carbon gets oxidised to carbon dioxide while the metal oxide gets reduced to its respective metal.
But for the metals that lie above carbon in the reactivity series, their respective oxides cannot be reduced by heating it with carbon dioxide. For extracting these metals, electrolytic reduction of their respective molten chlorides, oxides or hydroxides is performed. Let us explain the electrolytic reduction method with the help of an example. Sodium is extracted by electrolytic reduction of molten sodium chloride. When the current is passed through fused sodium chloride, sodium ion is reduced at the cathode while chloride ions are oxidised at the anode. The chemical reactions are given below:
At anode (negatively charge), $2N{a^ + } + 2{e^ - } \to 2Na(s)$
At cathode (positive charge), $2C{l^ - } \to C{l_2}(g) + 2{e^ - }$
Thus, these metals are more electropositive than carbon. Then, the metals which are highly electropositive are extracted by electrolytic reduction.

Hence correct answer is option A.

Note:
In the reactivity series of metals, metals are arranged from the most reactive to the least reactive or decreasing reactivity. This series is based upon the reactivity of different metals and non-metals which has been made after carefully observing their reactions with water, acids and other metallic compounds.