(d) Explain why there may be a maximum operating temperature for the column and also why there has to be temperature control of the injector. (e) Flame lonisation (FI), Mass Spectrometric (MS) and Thermal Conductivity (TC) can all be used as detection techniques in GC. Discuss the advantages and disadvantages of each as a detection method. Which method is used in combustion analysis? (f) A solution of volume 1 mL, containing an equal parts mixture (by weight) of propofol and di-tertbutylphenol (a standard), was analysed by GC, which displayed peaks at retention times 5.80 min (area integration 2000) and 9.20 min (area integration 3500), respectively. An unknown solution, also volume 1 mL, was analysed under the same conditions and, among a number of other peaks, there was one at 5.80 min (area integration 4000). How could this be confirmed as propofol? In a subsequent analysis, 2.5 mg of di-tertbutylphenol was dissolved in the unknown solution and an extra peak appeared in the GC at 9.20 min (area integration 2000). Assuming that the peak at 5.80 min had been confirmed as propofol, determine its concentration (g L-¹) in the unknown sample and estimate the error in the determination.

(d) Explain why there may be a maximum operating temperature for the column and also why there has to be temperature control of the injector. (e) Flame lonisation (FI), Mass Spectrometric (MS) and Thermal Conductivity (TC) can all be used as detection techniques in GC. Discuss the advantages and disadvantages of each as a detection method. Which method is used in combustion analysis? (f) A solution of volume 1 mL, containing an equal parts mixture (by weight) of propofol and di-tertbutylphenol (a standard), was analysed by GC, which displayed peaks at retention times 5.80 min (area integration 2000) and 9.20 min (area integration 3500), respectively. An unknown solution, also volume 1 mL, was analysed under the same conditions and, among a number of other peaks, there was one at 5.80 min (area integration 4000). How could this be confirmed as propofol? In a subsequent analysis, 2.5 mg of di-tertbutylphenol was dissolved in the unknown solution and an extra peak appeared in the GC at 9.20 min (area integration 2000). Assuming that the peak at 5.80 min had been confirmed as propofol, determine its concentration (g L-¹) in the unknown sample and estimate the error in the determination.

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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