Principles of Instrumental Analysis
7th Edition
ISBN: 9781305577213
Author: Douglas A. Skoog, F. James Holler, Stanley R. Crouch
Publisher: Cengage Learning
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Chapter 27, Problem 27.25QAP
Interpretation Introduction
Interpretation:
Percentages of each component should be calculated.
Concept introduction:
Area normalization method is used in quantitative analysis of compounds in chromatography. In this method of quantification, complete elution of all analytes in the sample is required. Following formulas are required for the calculation.
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One method for quantitative determination of the concentration of constituents in a sample analyzed by gas chromatography is the area normalization method. In this method, complete elution of all of the sample constituents is necessary. The area of each peak is then measured and corrected for differences in detector response to the different eluates. This correction is accomplished by dividing the area by an empirically determined correction factor. The concentration of the analyte is found from the ratio of its corrected area to the total corrected area of all peaks. For a chromatogram containing three peaks, the relative areas were found to be 16.4, 45.2, and 30.2 in the order of increasing retention time. Calculate the percentage of each compound if the relative detector responses were 0.60, 0.78, and 0.88, respectively
One method for the quantitative determination of the concentration of constituents in a sample analyzed by gas chromatography is area normalization. Here, complete elution of all the sample constituents is necessary. The area of each peak is then measured and corrected for differences in detector response to the different eluates. This correction involves dividing the area by an empirically determined correction factor. The concentration of the analyte is found from the ratio of its corrected area to the total corrected area of all peaks. For a chromatogram containing three peaks, the relative areas were found to be 16.4, 45.2 and 30.2, in order of increasing retention time. Calculate the percentage of each compound if the relative detector responses were 0.60, 0.78 and 0.88, respectively.
The response of the instrument must be lincar in the sample matrix.
Systematic errors can occur due to sample or standard preparation.
It consists of a series of standard analyte solutions separate from the unknown.
A blank is used to correct the response from the instrument.
Known quantities of a standard solution of the analyte are added to the unknown.
It is the method of choice when the matrix of the sample may affect the signal.
Matrix effects can cause the same analyte concentration in an unknown and standard to give different responses.
It is used to measure the instrument response as a function of a known analyte concentration under a set of conditions.
Chapter 27 Solutions
Principles of Instrumental Analysis
Ch. 27 - Prob. 27.1QAPCh. 27 - Prob. 27.2QAPCh. 27 - Prob. 27.3QAPCh. 27 - Prob. 27.4QAPCh. 27 - Prob. 27.5QAPCh. 27 - Prob. 27.6QAPCh. 27 - Prob. 27.7QAPCh. 27 - Prob. 27.8QAPCh. 27 - Prob. 27.9QAPCh. 27 - What are hyphenated GC methods? Briefly describe...
Ch. 27 - Prob. 27.11QAPCh. 27 - Prob. 27.12QAPCh. 27 - Prob. 27.13QAPCh. 27 - Prob. 27.14QAPCh. 27 - Prob. 27.15QAPCh. 27 - Prob. 27.16QAPCh. 27 - Prob. 27.17QAPCh. 27 - Prob. 27.18QAPCh. 27 - Prob. 27.19QAPCh. 27 - The same polar compound is gas chromatographed on...Ch. 27 - Prob. 27.21QAPCh. 27 - Prob. 27.22QAPCh. 27 - Prob. 27.23QAPCh. 27 - Prob. 27.24QAPCh. 27 - Prob. 27.25QAPCh. 27 - Prob. 27.26QAPCh. 27 - Prob. 27.27QAPCh. 27 - Prob. 27.28QAPCh. 27 - Why is GSC not used nearly as extensively as GLC?Ch. 27 - Prob. 27.30QAP
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