51. Solution to Chemistry Problem

2. The test solution contains an unknown mass of a-tocopheryl acetate and 10 mg of the internal standard sebacate. To determine the mass of α-tocopheryl acetate by capillary GLC, 5 model solutions were prepared with a given ratio of the mass m(ct) of the internal standard to the mass m of α-tocopheryl acetate, samples of these model solutions were chromatographed, the ratio of the areas Sct/S of the peaks of the internal standard and c-tocopheryl acetate was measured on the chromatograms and the following results were obtained:
m(ct)/m 0.248 0.307 0.354 0.378 0.503
S(cttys 0.212 0.264 0.305 0.319 0.427
A sample was taken from the analyzed solution, its chromatography was performed under the same conditions in which the chromatograms of the same solutions were recorded, the ratio S(ct)/S(x) of the peaks of the internal standard and α-tocopheryl acetate was measured and S(ct)/S(x) — 0.360.
Based on the data obtained, plot a calibration graph in the coordinates S(ct)/S - m(ct)/m, find the ratio m(ct)/m on the graph, and calculate the mass m(x), the standard deviation from the mean (with a sample size of 5 and a confidence level of 0.95). Using the correction factor, calculate the ratio m(ct)/m and the mass m(x) of a-tocopheryl acetate in the analyzed solution.