21. Solution to Chemistry Problem

1. Absorbing impurities are determined in the preparation "Phosphaden" (FS 42-1960-99). The optical density of a 0.001% solution of the preparation in a 0.01 mol/l hydrochloric acid solution is measured in a cuvette with a layer thickness of 10 mm at wavelengths of 250, 260 and 280 nm. A 0.01 mol/l hydrochloric acid solution is used as a comparison solution. The D250/D260 ratio should be from 0.80 to 0.87. The optical densities at wavelengths of 250 and 260 nm are 0.430 and 0.506, respectively.
The D280/D260 ratio is 0.231.
Calculate their ratio and determine whether it fits within the permissible amount. Calculate what the optical density should be at a wavelength of 280 nm