What chemical process is used for obtaining a metal from its oxide?

Explanation

(i) Metals low in the activity series are very unreactive. The oxides of these metals can be reduced to metals by heating alone.
`2HgO(s) overset("Heat")rarr 2Hg(I) + O(g)`
(ii) The metals in the middle of the activity series such as iron, zinc, lead, copper, etc., are moderately reactive. These metal oxides are reduced to the corresponding metals by using suitable reducing agents.
`ZnO(s) + C(s) rarr Zn(s) + CO(g)`
(iii) The metals high up in the reactivity series are very reactive. They are separated from their oxides by electrolysis process.