73. Solving a chemistry problem

78. Methods for determining the concentration of substances in photometry.
Calculate the minimum concentration of zirconium in mol/l and mg/l that can be determined photometrically with xylenol orange. The molar light absorption coefficient of this reaction at λ = 535 nm is 3.5*104, the measurements were carried out in a cuvette with l = 5 cm. The minimum optical density value determined with sufficient accuracy is 0.100.