Question

The addition of silica during the extraction of copper from its sulphide ore :- 

(1) converts copper sulphide into copper silicate 

(2) converts iron oxide into iron silicate 

(3) reduces copper sulphide into metallic copper 

(4) reduces the melting point of the reaction mixture

Answer 1

(2) converts iron oxide into iron silicate 

Silica is used to remove FeO impurity from the ore of copper

FeO + SiO₂ → FeSiO₃ iron silicate (Slag)