Page 36 - Instrumental Analysis - Pharm D Clinical- 07-PA403
P. 36

UV-visible Spectrophotometry

                           Problems

           • Absorbance of a sample solution equals 0.45 at λmax of 265 nm,
                ε = 381.6 L cm-1 mol-1, MW = 206.3. Calculate concentration in g% and
                ppm.

           • A standard solution containing 120 ppm KMnO4 (MW = 158) exhibits
                A = 0.443 in a 1.00 cm cell at 525 nm. Calculate the concentration (in
                ppm and molarity) of an unknown solution which gives A = 0.662 at
                the same λmax.
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