Question

The most common source of copper (Cu) is the mineral chalcopyrite (CuFeS2). How many kilograms of chalcopyrite must be mined to obtain 305 g of pure Cu? Express your answer to three significant figures and include the appropriate units.

Answer 1

Answer:

0.881 kilograms

Explanation:

Mass of $Cu$ = 305 g

Molar mass of $Cu$ = 63.546 g/mol

The formula for the calculation of moles is shown below:

$moles = \frac{Mass\ taken}{Molar\ mass}$

Thus,

$Moles= \frac{305\ g}{63.546\ g/mol}$

Moles of $Cu$ = 4.8 moles

Since in the formula of $CuFeS_2$,

1 mole of copper is present in 1 mole of $CuFeS_2$

So,

4.8 mole of copper is present in 4.8 mole of $CuFeS_2$

Moles of $CuFeS_2$ = 4.8 moles

Molar mass of $CuFeS_2$ = 183.53 g/mol

The formula for the calculation of moles is shown below:

$moles = \frac{Mass\ taken}{Molar\ mass}$

Thus,

$4.8\ moles= \frac{Mass}{183.53\ g/mol}$

Moles of $CuFeS_2$ = 881 g

Also, 1 g = 0.001 kg

So,

0.881 kilograms of chalcopyrite must be mined to obtain 305 g of pure Cu.