(a)
Interpretation:
The standard deviation for the chlorinated hydrocarbons in the air sample is 0.030ppm by using established method. The 95% confidence interval for the mean of the four measurement obtained by this method is to be determined.
Concept introduction:
The 95% confidence interval for each data is calculated as-
Where,
N = degree of freedom
s = standard deviation
t = constant
(b)
Interpretation:
The standard deviation for the chlorinated hydrocarbons in the air sample is 0.030ppm by using established method. The number of measurements is to be determined when 95% confidence interval is to be
Concept introduction:
The 95% confidence interval for each data is calculated as-
Where,
N = degree of freedom
s = standard deviation
t = constant
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Principles of Instrumental Analysis
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- Principles of Instrumental AnalysisChemistryISBN:9781305577213Author:Douglas A. Skoog, F. James Holler, Stanley R. CrouchPublisher:Cengage Learning
- Principles of Modern ChemistryChemistryISBN:9781305079113Author:David W. Oxtoby, H. Pat Gillis, Laurie J. ButlerPublisher:Cengage Learning