One of the following metals is obtained by leaching its ore with dilute cyanide solution, Identify it.
Options
(a) titanium
(b) vanadium
(c) silver
(d) zinc
Correct Answer:
silver
Explanation:
Cyanide process: ‘Mac Arthur – forest cyanide process.’ The powdered argentite ore is agitated with a dilute solution of NaCN(0.5%) while a current of O₂ is constantly passed. The metallic silver or silver from the ore dissolves forming sodium argentocyanide. 2Ag₂S +8NaCN + O₂ + 2H₂O → 4Na[Ag(CN)₂] + 4NaOH + 2S. The soluble silver complex is filtered and treated with zinc dust when silver gets precipitated. 2Na[Ag(CN₂)] + Zn →Na₂[Zn(CN)₄] + 2Ag↓.