Question

Arrange the following according to the instructions given in brackets :

(i) K, Pb, Ca, Zn. (In the increasing order of the reactivity)

(ii) Mg²⁺, Cu²⁺, Na¹⁺ , H¹⁺

(In the order of preferential discharge at the cathode)

Answer 1

(i) Pb < Zn < Ca < K

(According to the position in reactivity series)

(ii) Na¹⁺ < Mg²⁺ < H¹⁺ < Cu²⁺

(According to electrochemical series of metals)