114. Solving a chemistry problem

4. The molar light absorption coefficient of copper (2+) dithizonate in carbon tetrachloride at λ=550nm is 4.52*104. What mass fraction (%) of copper can be determined with dithizone if 25.00 ml of a solution of dithizonate in carbon tetrachloride is obtained from a sample of an alloy weighing 1.00 g and an optical density of 0.02 is measured in a 5.0 cm cuvette. Answer: 1.4 *10-5%.