49. Solving a chemistry problem

4. Calculate the concentration of sulfacetamide (sulfacyl sodium) in percent.
About 0.1 g (exact weight) of the analyzed medicinal substance (sulfacetamide) is placed in a 100 ml volumetric flask, dissolved in 50 ml of water and the volume is adjusted to the mark with the same solvent, mixed (solution A). Place 1 ml of solution A in a 100 ml volumetric flask, dilute the solution with water to the mark and mix (solution B).
The optical density of the obtained analyzed and standard solutions B is measured on a spectrophotometer at a wavelength of 261 nm in a cuvette with a layer thickness of 10 mm.
Water is used as a reference solution.
Preparation of a standard sample solution (GSO) of sulfacetamide. 0.1 g (accurately weighed) of sulfacetamide is placed in a volumetric flask with a capacity of 100 ml, dissolved in 50 ml of water and the volume is adjusted to the mark with the same solvent, mixed (solution A). Place 1 ml of solution A in a 100 ml volumetric flask, dilute the solution with water to the mark and mix (solution B).
The optical density of the test solution is 0.427; the optical density of the standard sample is 0.432, the exact weight of the preparation is 0.1010 g, the exact weight of the standard sample is 0.1015 g.
The optical density of the resulting standard solutions is measured on a spectrophotometer at a wavelength of 261 nm in a cuvette with a layer thickness of 10 mm.
Water is used as a reference solution.