36. Solving a chemistry problem

6. To determine sulfates in sodium chlorate, a series of standard solutions were prepared: V ml of sodium sulfate solution (T = 0.0739 g/ml) was introduced into volumetric flasks with a capacity of 50 ml, as well as reagents necessary to obtain a suspension of barium sulfate. Phototurbidimetric measurements of the optical density of these solutions gave the following results:
V, ml 0.4 0.8 1.2 1.6 2.0
Acaj 0.15 0.30 0.45 0.60 0.75
From a sample of sodium chlorate weighing 1.5250 g, 25 ml of a solution was prepared, 10 ml of which was transferred into a volumetric flask with a capacity of 50 ml, a suspension of barium sulfate was prepared, and the optical density was measured. Determine the mass fraction (%) of sulfate ions in sodium chlorate if Ax = 0.49.