Question

A student is performing displacement reactions of metals with salt solutions.
(a) In first case, the student keeps a strip of copper metal in iron (II) sulphate solution for a considerable time
(b) In second case, the student keeps a strip of zinc metal in copper (II) sulphate solution for a considerable time
(i) In which case the displacement reaction will take place? Why?
​(ii) In which case the displacement reaction will not take place? Why not?

Answer 1

(i) When a student keeps a strip of zinc metal in copper sulphate, displacement reaction will take place. Zinc is more reactive than copper sulphate, so zinc will displace copper from copper sulphate and form zinc sulphate.

$\mathrm{Zn}\left(\mathrm{s}\right)+{\mathrm{CuSO}}_4\left(\mathrm{aq}\right)\to {\mathrm{ZnSO}}_4\left(\mathrm{aq}\right)+\mathrm{Cu}\left(\mathrm{s}\right)$

(ii) When a student keeps a strip of copper metal in iron sulphate, no reaction will take place. Copper is less reactive than iron so it will not be able to displace iron from iron sulphate.

$\mathrm{Cu}\left(\mathrm{s}\right)+{\mathrm{FeSO}}_4\left(\mathrm{aq}\right)\to \mathrm{No}\mathrm{reaction}$