145. Задачка по химии №014 5419

34. A weight of steel weighing 0.2500 g was dissolved in a mixture of acids, transferred to a volumetric flask with a capacity of 100.00 ml, diluted to the mark with water, mixed. Hydrogen peroxide, phosphoric acid was added to 25.00 ml of the obtained solution to determine titanium, diluted with distilled water to a volume of 50.00 ml. The optical density of the resulting solution is equal to 0,220. To another portion of the solution of 25.00 ml, 0.20 mg of titanium was added, treated similarly to the first. The optical density of this solution was equal to 0.500. What is the mass fraction (%) of titanium in the alloy?