WAEC Chemistry 2015 Paper

Concept:The strongest reducing agent is the metal that most easily loses electrons, shown by the most negative standard electrode potential.Explanation:Potassium, $\mathrm{K}$, has the most negative standard electrode potential among the given metals.Its value is about $-2.93\ \mathrm{V}$, while sodium is about $-2.71\ \mathrm{V}$.Silver and copper have positive standard electrode potentials.Therefore, $\mathrm{K}$ has the greatest tendency to lose electrons and act as a reducing agent.Answer:C. Potassium