Question

Sulphide ores of metals are usually concentrated by froth flotation process. Which one of the following sulphide ores offer an exception and is concentrated by chemical leaching? 

(1) Galena 

(2) Copper pyrite 

(3) Sphalerite 

(4) Argentite

Answer 1

Leaching is the selective discharge of the desired mineral leaving behind the impurities in a suitable dissolving agent, for example, argentite or silver glance, Ag₂S is an ore of silver. Silver is extracted from argentite by the MacArthur Forest process (leaching process). 

Hence, the correct option is (4).