51. Solving a chemistry problem

2. When determining molybdenum by the method of additions, a sample of steel m = 0.7468 g was dissolved, the volume of the solution was brought to 50 ml. Then 20 ml aliquots of this solution were withdrawn into 50 ml volumetric flasks. A standard solution of molybdenum was added to one of them, after which its concentration (Cst) became equal to 1.18 10–3 mol/l. Hydrogen peroxide was added to both flasks and the volume was brought to the mark, photometrically and obtained Ax = 0.25 and Ax st = 0.50. Calculate the percentage of molybdenum in steel.