Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

One way in which the useful metal copper is produced is by dissolving the minera

ID: 501359 • Letter: O

Question

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) + CuSO_4(aq) rightarrow Cu(s) + FeSO_4(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 300. 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 88. mg. Calculate the original concentration of copper(II) sulfate in the sample.

Explanation / Answer

Fe (s) + CuSO4 (aq) -------------> FeSO4 (aq) + Cu (s)

mass of Cu = 88.0 mg = 0.088 g

moles of CuSO4 = moles of Cu = 0.088 / 63.55

                           = 1.38 x 10^-3 mol

volume of solution = 300 mL

conentration of CuSO4 = 1.38 x 10^-3 / 0.3

                                     = 4.62 x 10^-3 M

  conentration ofCuSO4 = 0.29 g/L