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 9, Problem 9.22QAP
The chromium in an aqueous sample was determined by pipetting 10.0 ml. of the unknown into each of five 50.0-mL volumetric flasks. Various volumes of a standard containing 12.2 ppm Cr were added to the flasks,
following which the solutions were diluted to volume.
Unknown,mL Standard, mL Absorbancc
10.0 0.0 0.201
10.0 10.0 0.292
10.0 20.0 0.378
10.0 30.0 0.467
10.0 40.0 0.554
(a) Plot the data using a spreadsheet.
(b) Determine an equation for the relationship between absorbance and volume of standard.
(c) Calculate the statistics for the least-squares relationship in (b).
(d) I)ctcrmine the conccnt ration oÍCr in ppm in the sample.
(e) Find the standard deviation of the result in (d).
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Chapter 9 Solutions
Principles of Instrumental Analysis
Ch. 9 - Prob. 9.1QAPCh. 9 - Prob. 9.2QAPCh. 9 - Why is an electrothermal atomizer more sensitive...Ch. 9 - Prob. 9.4QAPCh. 9 - Prob. 9.5QAPCh. 9 - Prob. 9.6QAPCh. 9 - Prob. 9.7QAPCh. 9 - Prob. 9.8QAPCh. 9 - Prob. 9.9QAPCh. 9 - Prob. 9.10QAP
Ch. 9 - Prob. 9.11QAPCh. 9 - Prob. 9.12QAPCh. 9 - Prob. 9.13QAPCh. 9 - Prob. 9.14QAPCh. 9 - Prob. 9.15QAPCh. 9 - Prob. 9.16QAPCh. 9 - Prob. 9.17QAPCh. 9 - In the concentration range of 1 to 100 g/mL P,...Ch. 9 - Prob. 9.19QAPCh. 9 - Prob. 9.20QAPCh. 9 - Prob. 9.21QAPCh. 9 - The chromium in an aqueous sample was determined...Ch. 9 - Prob. 9.23QAP
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