Principles of Instrumental Analysis
7th Edition
ISBN: 9781337468039
Author: Skoog
Publisher: Cengage
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Chapter 32, Problem 32.12QAP
Interpretation Introduction
Interpretation:
The relative standard of counting rate
Concept introduction:
The counting rate is calculated by the following formula-
And standard deviation for counting rate is given as-
Standard deviation is-
Relative standard deviation is for counting rate =
Where,
M = counts
t = time
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For the determination of iron in used jet engine oil, 30 analyzes with 3 repetitions each were made by atomic absorption method and the standard deviation was found s=2.4 µg Fe/mL. Since this standard deviation value is close to the ϭ value, the iron concentration of 18.5 µg Fe/mL(a) by a single analysis,(b) as the average of the two analyzes,(c) Calculate the 80% and 95% confidence intervals if found as the mean of four analyses.
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Chapter 32 Solutions
Principles of Instrumental Analysis
Ch. 32 - Identify X in each of the following nuclear...Ch. 32 - Prob. 32.2QAPCh. 32 - Prob. 32.3QAPCh. 32 - Prob. 32.4QAPCh. 32 - Prob. 32.5QAPCh. 32 - Prob. 32.6QAPCh. 32 - Prob. 32.7QAPCh. 32 - Prob. 32.8QAPCh. 32 - Prob. 32.9QAPCh. 32 - Prob. 32.10QAP
Ch. 32 - Prob. 32.11QAPCh. 32 - Prob. 32.12QAPCh. 32 - Prob. 32.13QAPCh. 32 - Prob. 32.14QAPCh. 32 - Prob. 32.15QAPCh. 32 - Prob. 32.16QAPCh. 32 - Prob. 32.17QAPCh. 32 - The streptomycin in 500 g of a broth was...Ch. 32 - Show, via a calculation, that the average kinetic...Ch. 32 - Prob. 32.20QAPCh. 32 - Prob. 32.21QAP
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