0731. Solving a chemistry problem

9. Calculate the % content of rutin in the substance rutin, if a sample of the substance weighing 0.0502 g, previously dried at a temperature of 130 - 135 C for 3 hours, was dissolved in 85 ml of 96% alcohol in a 100 ml volumetric flask when heated in a water bath , cooled, brought the volume of the solution to the mark with the same alcohol and mixed (solution A). 1.0 ml of solution A, 2 ml of aluminum chloride alcohol solution 2%, 0.1 ml of acetic acid diluted 30% were transferred to a 25 ml volumetric flask and brought to the mark with 96% alcohol (solution B). The optical density of solution B at a wavelength of 415 nm was 0.497. The specific absorption index of the rutin complex with aluminum chloride at a wavelength of 415 nm is 248.