Zinc can be coated on iron to produce galvanized iron,but the reverse is not possible. This is because:

The standard reduction potentials for $Cu^{2+}|Cu$ and $Cu^{2+}|Cu^{+}$ are $0.337 \, V$ and $0.153 \, V$ respectively. What is the standard electrode potential for the $Cu^{+}|Cu$ half-cell in $V$?

Given the standard reduction potentials at $25\,^oC$ for the following half-reactions:
$Zn^{2+}_{(aq)} + 2e^- \rightleftharpoons Zn_{(s)}, E^o = -0.76\,V$
$Cr^{3+}_{(aq)} + 3e^- \rightleftharpoons Cr_{(s)}, E^o = -0.74\,V$
$2H^+_{(aq)} + 2e^- \rightleftharpoons H_{2(g)}, E^o = 0.00\,V$
$Fe^{3+}_{(aq)} + e^- \rightleftharpoons Fe^{2+}_{(aq)}, E^o = +0.77\,V$
Which of the following is the strongest reducing agent?

What does the negative sign in the expression $E_{Zn^{2+}|Zn}^o = -0.76 \ V$ mean?

What is the value of the standard electrode potential of a standard hydrogen electrode $(SHE)$ (in $V$)?

Reduction of species is dependent on its reduction potential value.