The chelate CuA22- exhibits maximum absorption at 480 nm. When the chelating reagent is present I at least a tenfold excess, the absorbance depends only on the analytical concentration of Cu(II) and conforms to Beer's law over a wide range. A solution in which the analytical concentration of Cu2+ is 2.15×10-4 M and that for A2- is 9.00×10-3 M has an absorbance of 0.759 when measured in a 1.00-cm cell at 480 nm. A solution in which the analytical concentrations of Cu2+ amd A2- are 2.15 ×10-4 M and 4.00×10-4 M, respectively, has an absorbance of .654 when measured under the same conditions. Use this information to calculate the formation constant kt for the process
