You are analyzing a forensic sample for the presence of controlled substances using HPLC. Which ofthe following detectors would be the best one to use to confirm the identities of the substances inthe sample?UVevaporative light scatteringrefractive indexelectrochemicalMS Look at Figure below which represents a gas chromatogram obtained at 40° C. If youchromatographed the same sample at 25° C how would the chromatogram change?Detector responseSolvents1 15HO -K2,3-Dimethyl-2-butanol1-Butanol101151-Pentanol20125Time (min)the peaks would be closer togetherthe peaks would be larger in areathe peaks would be farther apart30the peaks would be smaller in area351-Hexanol^InjectionFigure 24-8 Chromatogram of alcohol mixture at 40°C using packed column(2 mm inner diameter x 76 cm long) containing 20% Carbowax 20M on Gas-Chrom Rsupport and flame ionization detector. [Courtesy Norman Pearson.)4045

You are analyzing a forensic sample for the presence of controlled substances using HPLC. Which of the following detectors would be the best one to use to confirm the identities of the substances in the sample? O UV evaporative light scattering refractive index electrochemical

You are analyzing a forensic sample for the presence of controlled substances using HPLC. Which of the following detectors would be the best one to use to confirm the identities of the substances in the sample? O UV evaporative light scattering refractive index electrochemical

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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The absorbance of a cationic iron(II) sample solution was measured in a spectrophotometer, but the instrument returned an error because the absorbance was too high. The sample was then diluted by using a pipette to take 100.0 μLμL of the sample and injecting it into a cuvette already containing 2.00 mLmL of water (total volume is 2.00 mLmL + 100.0 μLμL). The absorbance value of the diluted solution corresponded to a concentration of 7.71×10−6 M M . What was the concentration of the original solution? Express the concentration to three significant figures with the appropriate units.
Sel Absorbance S Verify your molar absorptivity value. Did you report your data to the correct number of significant figures? Analytical wavelength Analytical wavelength for blue dye (nm) Calibration curve Solution 1 2 3 4 5 Dye concentration (μM) 15.20 7.51 Unknown solution 3.74 1.89 1.01 Molar absorptivity (μM ¹cm-¹) Absorbance Concentration of unknown blue dye (µM) 629 Absorbance 0.756 0.432 0.259 0.175 0.144 0.083 How to calculate concentration from absorbance S A d tra 01
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After determining the absorbance of several standards of known concentration, the trendline for a calibration curve (AKA a standard curve) plotting absorbance (y-axis) against concentration (M, x-axis) is determined to be y = 4.943x + -0.0001 The absorbance of a solution of unknown concentration is determined to be 0.48. Calculate the concentration of the unknown solution in M. Give your answer to three decimal places.
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