(a) What is reactivity series ? How does the reactivity series of metals help in predicting the relative activities of various metals ?
(b) Suggest different chemical processes used for obtaining a metal from its oxides for metals in the middle of the reactivity series and metals towards the top of the reactivity series. Support you answer with one example each.

Explanation

(i) For obtaining metals that are in the middle of the reactivity series, oxides of such metals can be reduced with coke (carbon) which acts as a reducing agent. (ii) For obtaining metals that are high in the reactivity series, their oxides are reduced to metals by the process of electrolysis.
Example : Electrolysis of sodium chloride.
At cathode : `Na^(+) + e^(-) rarr Na`
At anode : `2Ci^(-) rarr CI_(2) + 2e^(-)`