In the Background section, it says that the "copper(II) concentration in the Cu(103)2(S) Cu+ (aq) + 2103(aq) equilibrium solution can be determined spectroscopically; it tells you that you will determine the Cu+ concentration in the equilibrium solution using a Beer's Law plot of absorbance versus concentration and the iodate concentration from the balanced dissolution equation, Cu(103)2(s) Cu+(aq) + 2103 (aq), and the copper ion concentration in the equilibrium mixture