52. Solution to Chemistry Problem

32.2 From 5.0 cm3 of ZnCl2 solution with T ZnCl2/Zn 2 μg/cm3 zinc was extracted with 10.0 cm3 of carbon tetrachloride. The optical density of the extract at 535 nm was 0.418 in a 3-cm cuvette. To another portion of ZnCl2 solution also equal to 1.0 cm3 was added 10.0 cm3 of the analyzed water sample, all operations were performed. The optical density of the extract was 0.624. Determine the zinc content in the water (in mg/dm3).