Chemistry problem g/L

Question

What is the answer to this problem?

One way in which the useful metal copper is produced is by dissolving the mineral azurite, which contains copper(II) carbonate, in concentrated sulfuric acid. The sulfuric acid reacts with the copper(II) carbonate to produce a blue solution of copper(II) sulfate. Scrap iron is then added to this solution, and pure copper metal precipitates out because of the following chemical reaction:

Fe(s) + CuSO4(aq) → Cu(s) + FeSO4(aq)

Suppose an industrial quality-control chemist analyzes a sample from a copper processing plant in the following way. He adds powdered iron to a 150.mL copper(II) sulfate sample from the plant until no more copper will precipitate. He then washes, dries, and weighs the precipitate, and finds that it has a mass of 137.mg. Calculate the original concentration of copper(II) sulfate in the sample. Round your answer to 3

 significant digits.

Answer 1

1. Convert 137 mg of Copper to grams
2. 137 mg Cu x (1g Cu / 1000 mg Cu) = 0.137 g Cu
3. Convert grams of Cu to moles (Molar Mass Cu = 63.55 g/mol)
4. 0.137 g Cu x (1 moles Cu / 63.55 g Cu) = 0.00216 moles Cu
5. Use Stoichiometry to find moles of CuSO₄:
6. Fe(s) + CuSO4(aq) → Cu(s) + FeSO4(aq)
7. 0.00216 mol 0.00216 mol
8. Convert moles of CuSO₄ to grams (Molar Mass CuSO₄ = 159.61 g/mol)
9. 0.00216 mol CuSO₄ x (159.61 g/mol CuSO₄) = 0.345 g CuSO₄
10. Use concentration equation (Concentration = g/L):
11. 150 mL CuSO₄ x (1 L / 1000 mL CuSO₄) = 0.150 L CuSO₄
12. Concentration = (0.345 g / 0.150 L CuSO₄) = 2.30 g/L CuSO₄