3. What experimental problems would confront you if you attempted to determine the concentration of the metal ions in solutions of each of the following reagents?
a. Cr +3 which has a maximum absorbance at 407 nm with absorbtivity of 15 M -1 cm -1 and another at 574 nm with absorbtivity of 13 M-1 cm -1
b. Mn 2+ which has a maximum absorbance at 530 nm with absorbtivity of .050 M - 1 cm -1.