Assuming complete recovery of metal, which of the following ores would yield a greater quantity of copper ?
(a) An ore azurite `(Cu(OH)_(2).2CuCO_(3))` containing 3.30% (by mass)
(b) An ore chalcopyrite `CuFeS_(2)` containing 4.95% (by mass).

Explanation

(a) `Cu(OH)_(2).2CuCO_(3)=3`
`3xx63.5+2+12+8xx16+2xx13xx63.5=190.5g`.
=344.5 g
344.5 g of ore contain Cu =190.5g
0.033 g of ore contains `Cu=((190.5g))/((344.5g))xx(0.033g)=0.0182g`
(b) `CuFeS_(2)-=Cu`
`63.5+56+2xx32=63.5g`
0.0495g of ore contains `Cu=((63.5g))/((183.5g))xx(0.0495g)=0.171 g`
The ore azurite contains greater amount of copper.