Question

A student was asked to carry out a chemical reaction by placing four different metal strips in CuSO₄ solution for a considerable time, one by one. Which of the following metal strip will turn the blue CuSO₄ solution to a colourless solution in due course of time?
(1) Fe
(2) Au
(3) Mg
(4) Ag

Answer 1

Out of all the given options, magnesium is most reactive so that it will displace the Cu from CuSO₄ solution.
$\mathrm{Mg}\left(\mathrm{s}\right)+2{\mathrm{CuSO}}_4\left(\mathrm{aq}\right)\to \mathrm{Mg}({\mathrm{SO}}_4{)}_2+2\mathrm{Cu}(\mathrm{s})$

Hence, the correct answer is option 3.