2. Solving a chemistry problem

6. When determining vanadium by the addition method, a 0.5 g sample of steel was dissolved, and the volume of the solution was brought to 50.00 ml. Then, 20.00 mL aliquots of the solution were collected into two 50.00 mL volumetric flasks. A portion of vanadium salt was added to one of them. containing 1.0*10-3 g. The samples were oxidized and brought to the mark in the flask. Calculate the percentage of vanadium in steel if the following data were obtained during photometry: D = 0.20, Dx st = 0.48.