JEE Main 2021 — Electrochemistry Question with Solution

In the electrode potential series, only copper have positive value for electrode potential because copper has lower tendency than hydrogen to form ions. So, if standard hydrogen electrode (E_Cell = 0) is connected to copper half-cell, the copper with be relatively less negative or less number of electrons.

$$E_{(C{u}^{2+}/Cu)}^o$$ = + 0.34 V; $$E_{(F{e}^{2+}/Fe)}^o$$ = $$-$$ 0.41 V

$$E_{(C{o}^{2+}/Co)}^o$$ = $$-$$ 0.28 V; $$E_{(Z{n}^{2+}/Zn)}^o$$ = $$-$$ 0.76 V

$$\therefore$$ Electrode potential of Cu $$E_{(C{u}^{2+}/Cu)}^o$$ show positive value.