Question

What happens when a nickle rod is dipped into a copper sulphate solution? Justify your answer. $[E_{N{i}^{+2}/Ni}^0=-0.25$v and $E_{C{u}^{+2}/Cu}^0=+0.34v]$.

Answer 1

Red copper metal starts precipitating. This is because $E_{N{i}^{+2}/Ni}^0$ is less than $E_{C{u}^{+2}/Cu}^0$. So, Ni displace $C{u}^{+2}$ ions from the solution. $\underset{metal}{Ni}+C{u}_{\left(aqu\right)}^{+2}\to N{i}_{\left(aqu\right)}^{+2}+\underset{metal}{Cu}$.