The most common copper ore used in the production of copper is chalcopyrite. If a chalcopyrite ore contains 55.0% CuFeS2, how many grams of chalcopyrite ore are needed to produce 60.0 g of copper?

Answer is: 315,29 grams of copper ore.

m (chalcopyrite) = ?

ω (CuFeS₂) = 55,0 % = 0,55.

m (Cu) = 60,0 g.

mass percentage of copper in CuFeS₂:

ω (Cu) = Ar (Cu) : Mr (CuFeS₂).

ω (Cu) = 63,55 : 183,4.

ω (Cu) = 0,346 = 34,6 %.

mass percentage of copper in chalcopyrite:

ω (Cu) : ω₁ (Cu) = 100% : ω (CuFeS₂).

ω₁ (Cu) = 19,03 % = 0,1903.

m (chalcopyrite) = 60,0 g : 0,1903.

m (chalcopyrite) = 315,29 g.