Question

Cooper can be extractted by hydrometallurgy but not zinc Explain.

Answer 1

$E^{\circ }valueofZ{n}^{2+}/Zn=-0.76$ V is less than that of $C{u}^{2+}/Cu=+0.34$ V. It means that zinc is a stronger reducintg agent and can easily displace the $C{u}^{2+}$ iions present in he complex .
$\left[Cu\right(CN{)}_2]+Zn⟶[Zn\left(CN{)}_2\right]+Cuppt$

So Zinc can be isolated by hydrometallurgy only when stronger reducing agents than zinc (Ca, Mg, Al, etc, ) are present. But these react with water to evolve hydrogen gas. Thus, rhese metals also don not solve the purpoose and zinc cannot be extracted by hydrometallurgy,