Principles of Instrumental Analysis
7th Edition
ISBN: 9781337468039
Author: Skoog
Publisher: Cengage
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Chapter 1, Problem 1.9QAP
Interpretation Introduction
Interpretation:
The molar concentration of
Concept introduction:
Calibration of instrumental methods: The purpose of calibration which is required by all types of analytical methods is quantitation. It is defined as a process in which the measured analytical signal and the concentration of analyte are related to each other. The three most common methods to calibrate are:
- Calibration curve.
- Standard addition method.
- Internal standard method.
In case of standard addition method, standards are added to the aliquots of sample, keeping the matrix components same. On each solution, instrumental measurements are made to obtain instrument response ( S ).
The relation between the instrument response and concentration if they are proportional is,
Where,
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