Question

Identify the reaction from following having top position in EMF series (Std. red. potential) according to their electrode potential at 298 K.

(1) K⁺ + 1e^– → K_(s)

(2) Mg²⁺ + 2e^– → Mg_(s)

(3) Fe²⁺ + 2e^– → Fe_(s)

(4) Au³⁺ + 3e^– → Au_(s)