Q4) (a) Explain how the components of a mixture are separated in gas chromatography. (b) An aqueous solution whose concentration is 0.00356 M was analyzed using spectrophotometer with a molar absorptivity of 412 cm-1 mol-1 L in a cell with a 2.00 cm pathlength. Calculate the absorbance and transmittance for the above solution. (c) Analyze the reasons why a dropping mercury electrode is better as compared to a conventional electrode.

Q4) (a) Explain how the components of a mixture are separated in gas chromatography. (b) An aqueous solution whose concentration is 0.00356 M was analyzed using spectrophotometer with a molar absorptivity of 412 cm-1 mol-1 L in a cell with a 2.00 cm pathlength. Calculate the absorbance and transmittance for the above solution. (c) Analyze the reasons why a dropping mercury electrode is better as compared to a conventional electrode.

Principles of Instrumental Analysis

7th Edition

ISBN:9781305577213

Author:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Publisher:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Chapter1: Introduction

Section: Chapter Questions

Problem 1.9QAP

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What is the resolution in ppm NO3-N of a spectrophotometer that gives a reading of 0.600 absorbance units for 25 ppm NO3-N? The resolution of the instrument is 0.001 absorbance units.
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(a) You measure the percent transmittance of a solution containing chromophore X at 400nm in a 1-cm path length cuvette and find it to be 50%. What is the absorbance of this solution? (b) What is the molar absorptivity of chromophore X if the concentration of X in the solution measured in question (a) is 0.5mM? (c) What is the concentration range of chromophore X that can be assayed if, when using a sample cell of path length 1, you are required to keep the aborbance between 0.2 and 0.8?
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