Chemistry - General Principles and Processes of Isolation of Metals Question with Solution | TestHub

Cyanide process, which is also known as MacArthur cyanide process involves the extraction of gold and silver from their ores by dissolving them in a dilute solution of sodium cyanide or potassium cyanide. The leaching is carried out in the presence of air or oxygen to oxidise the metal.

$\mathrm{Ag}$ is leached by cyanide process by making the complex using $\mathrm{NaCN}/\mathrm{KCN}$ as follows

${\mathrm{Ag}}_2\mathrm{S}+4\mathrm{NaCN}⟶2\underset{\mathrm{Soluble}}{\mathrm{Na}\left[\mathrm{Ag}(\mathrm{CN}{)}_2\right]}+{\mathrm{Na}}_2\mathrm{S}$