The most common source of copper (Cu) is the mineral chalcopyrite (CuFeS2). How many kilograms of chalcopyrite must be mined to obtain 315 of pure ?
of pure WHAT?
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To find out how many kilograms of chalcopyrite must be mined to obtain 315 kg of pure copper (Cu), we need to consider the composition of chalcopyrite and the molar mass of copper.
The formula for chalcopyrite is CuFeS2, which means it contains one atom of copper (Cu), one atom of iron (Fe), and two atoms of sulfur (S).
We need to calculate the molar mass of chalcopyrite by considering the atomic masses of each element:
- Atomic mass of copper (Cu) = 63.55 g/mol
- Atomic mass of iron (Fe) = 55.85 g/mol
- Atomic mass of sulfur (S) = 32.07 g/mol
Now we can calculate the molar mass of chalcopyrite:
Molar mass of chalcopyrite = (63.55 g/mol) + (55.85 g/mol) + 2 * (32.07 g/mol)
= 63.55 g/mol + 55.85 g/mol + 64.14 g/mol
= 183.54 g/mol
To find out how many moles are needed to obtain 315 kg of pure copper, we can use the molar mass of copper (Cu) to convert from kilograms to moles:
Moles of copper = (Mass of copper) / (Molar mass of copper)
The molar mass of copper (Cu) is 63.55 g/mol. We can convert 315 kg to grams by multiplying by 1000:
Mass of copper = 315 kg * 1000 g/kg = 315000 g
Now we can calculate the moles of copper:
Moles of copper = (315000 g) / (63.55 g/mol)
= 4957.77 mol (rounded to five decimal places)
Since the ratio of copper to chalcopyrite in the formula CuFeS2 is 1:1, we need an equal number of moles of chalcopyrite to obtain the desired amount of copper.
Therefore, to find the number of kilograms of chalcopyrite needed, we can use the molar mass of chalcopyrite:
Mass of chalcopyrite = (Moles of copper) * (Molar mass of chalcopyrite) / 1000
Substituting the values we have calculated:
Mass of chalcopyrite = (4957.77 mol) * (183.54 g/mol) / 1000
= 908.46 kg (rounded to two decimal places)
So, approximately 908.46 kg of chalcopyrite must be mined to obtain 315 kg of pure copper.