0.3414 grams of sample (crushed aspirin tablet) was weighed and dissolved in 25 mL ethanol. This solution was transferred into a 100 mL volumetric flask and filled to the mark with deionized water. 20 mL of the solution was filtered through a 0.22 μm pore filter and 503 μL of the filtered sample solution was diluted so, that the final volume of the solution was 12 mL. This sample solution and calibration solutions with known concentration of acetyl salicylic acid (ASA) were injected (injection volume 20 μL) into a HPLC and the following peak areas were measured (expressed as averages from three separate chromatographic runs): Solution Cal 1 Cal 2 Cal 3 Cal 4 Cal 5 Sample Structure of ASA: C(ASA) (mg/L) 0 OH B 53.5 105.9 140.9 195.4 247.4 Average weight of the tablet was estimated as 591.9 mg. What is the mass of ASA in one tablet? Please give the answer with 4 significant digits. Be sure you present the result with units! Peak area (mA.s) 4995 9953 12941 17271 22179 10467.3

0.3414 grams of sample (crushed aspirin tablet) was weighed and dissolved in 25 mL ethanol. This solution was transferred into a 100 mL volumetric flask and filled to the mark with deionized water. 20 mL of the solution was filtered through a 0.22 μm pore filter and 503 μL of the filtered sample solution was diluted so, that the final volume of the solution was 12 mL. This sample solution and calibration solutions with known concentration of acetyl salicylic acid (ASA) were injected (injection volume 20 μL) into a HPLC and the following peak areas were measured (expressed as averages from three separate chromatographic runs): Solution Cal 1 Cal 2 Cal 3 Cal 4 Cal 5 Sample Structure of ASA: C(ASA) (mg/L) 0 OH B 53.5 105.9 140.9 195.4 247.4 Average weight of the tablet was estimated as 591.9 mg. What is the mass of ASA in one tablet? Please give the answer with 4 significant digits. Be sure you present the result with units! Peak area (mA.s) 4995 9953 12941 17271 22179 10467.3

Appl Of Ms Excel In Analytical Chemistry

2nd Edition

ISBN:9781285686691

Author:Crouch

Publisher:Crouch

Chapter4: Least-squares And Calibration Methods

Section: Chapter Questions

Problem 1P

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