question

(i) write the role of  'co' in the purification of nickel.

(ii) what is the role of silica in the extraction of copper ?

(iii) what type of metals are generally extracted by electrolytic method ?

 

 

 

 

 

 

 

 

(i)forms a volatile complex nickel tetracarbonyl,leaving behind impurities. the nickel tetracarbonyl complex is heated to a higher temperature, decomposes to give pure metal.

(ii) silicaacts as a flux, added before roasting to combine with

[impurity] and form [slag]

(iii) very highly reactive metals like sodium, potassium,calcium etc are generally extracted by electrolytic method.