Question

= O STOICHIOMETRY Solving for a reactant in solution 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 100. 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 68. mg. Calculate the original concentration of copper(II) sulfate in the sample. Round your answer to 2 significant digits. 109 F x 6 ?

Answer 1

Sol) Here, the precipitate is Culs) Molar mass of Culs) = 63.546 g/mol Molar mass of Cusou (aq) = 159.609 g/mol Mass of Cu (s) = 68 g = 68x10-3g Moles of Cu (s) = (68x10^?g)/(63.546 g/mol) = 0.00107 moles curs) Volume of Cusou (aq.) = 100 ml = 100 x10-3L = 0.12 from the balanced reachion, Fecs) + Cusoylaq.) → Cu(s) + Fe soylaq;) Mass of Cuso 4 = 0.00107 mobs Culs) x 1 mole cusoul aq;) x / 159.609 g Cusou I mote Culs) I mole Casoy = 0.170 g cuson since the expected answer has units of g so we will not use molarity to denote concentration: So concentrahon lin 3/2) = 0.1409 - 17912) O.IL