# 6.1 Copper can be extracted by hydrometallurgy but not zinc. Explain.

$Zn(s)+Cu^{2+}(aq)\rightarrow Zn^{2+}(aq)+Cu(s)$
But to reduce zinc from its solution we need higher reactive metal, which reduction potential is lower than zinc like  $Al,Mg,Ca,K$ But these metals readily react with water with the evolution of  $H_{2}$ gas. As a result, these metals are cannot use to displace zinc ion from its solution.
$2K(s)+2H_{2}O(l)\rightarrow KOH(aq)+H_{2}(g)$