Question

How is leaching carried out in case of low grade copper ores?

Answer 1

In case of low grade ores of copper, hydrometallurgy is used for extraction purposes. Leaching is done by using acid or bacteria. The solution containing $C{u}^{2+}$ is treated with scrap iron or $H_2$

$C{u}^{2+}\left(aq\right)+H_2\left(g\right)⟶Cu\left(s\right)+2H^{+}\left(aq\right)$