Question

Chalcopyrite (CuReS2) is the principle one of copper and the iron contained is an important byproduct. The silver, however, is burned in oxygen to produce suffer dioxide, an environmental pollutant.

1.) Calculate the number of grams of copper contained in 30.0 kilograms of pure chalcopyrite.

2.) At $0.03 per gram for iron, how much would the iron extracted from the same 30 kilograms of chalcopyrite be worth?

3.) How many grams of silver dioxide will be produced during the conversion of 30.0 kilograms of chalcopyrite one to metallic copper and iron?

Answer 1

1) CuFeS2 has molar mass 183.54 g/mol

Molaes of chalcopyrite = mass/ molar mass = ( 30 x 1000 g) / ( 183.54 g/mol) = 163.45

Mass of Copper = moles x atomic mass of Cu = 163.45x 63.546 = 10387 g = 10.387 kg

2) Iron mass = moles x atomic mass of iron = 163.45 x 55.845 = 9127.86 g

cost of iron = mass of iron x 0.03 $ = 9127.86 x 0.03 = 273.84 $ = 274 $

3) SO2 moles produced = 2 x Cahlcopyrite moles   ( 1 CuFes2 gives 2SO2)

              = 2 x 163.45 = 326.9

SO2 mass = moles x amolar mass = 326.9 x 64.066 = 20943 g