Determining the sodium concentration in coffee with flame atomic absorption spectroscopy (FAAS) can be challenging due to interferences. To overcome these interferences, lithium is commonly used as an internal standard. A researcher prepared a sample with an internal standard (Lit) to analyte (Na+) concentration ratio of 2.00/1.00. The ratio of the internal standard signal to the analyte signal (Li+ signal/Na+ signal) was found to be 1.170/1.000. Determine the response factor, F. F = A sample was then prepared containing 12.70 mL of coffee and 4.80 mL of 5.20 ppm Lit, and diluted to a 50.00 mL total volume. The ratio of the internal standard signal to the analyte signal in the unknown sample was found to be 0.890/1.000 (Li+ signal/Na+ signal). Determine the unknown concentration of Na+ in the coffee sample. [Na+] = ppm

Determining the sodium concentration in coffee with flame atomic absorption spectroscopy (FAAS) can be challenging due to interferences. To overcome these interferences, lithium is commonly used as an internal standard. A researcher prepared a sample with an internal standard (Lit) to analyte (Na+) concentration ratio of 2.00/1.00. The ratio of the internal standard signal to the analyte signal (Li+ signal/Na+ signal) was found to be 1.170/1.000. Determine the response factor, F. F = A sample was then prepared containing 12.70 mL of coffee and 4.80 mL of 5.20 ppm Lit, and diluted to a 50.00 mL total volume. The ratio of the internal standard signal to the analyte signal in the unknown sample was found to be 0.890/1.000 (Li+ signal/Na+ signal). Determine the unknown concentration of Na+ in the coffee sample. [Na+] = ppm

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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