A chemist obtained the following data for percent lindane in the triplicate analysis of an insecticide preparation: 7.23, 6.95, and 7.53. Calculate the 95% confidence interval for the mean of the three data, assuming the following criteria. (a) the only information about the precision of the method is the precision for the three data Confidence interval = ± % lindane (b) on the basis of long experience with the method, it is believed that s --> o = 0.26% lindane Confidence interval = ± % lindane

A chemist obtained the following data for percent lindane in the triplicate analysis of an insecticide preparation: 7.23, 6.95, and 7.53. Calculate the 95% confidence interval for the mean of the three data, assuming the following criteria. (a) the only information about the precision of the method is the precision for the three data Confidence interval = ± % lindane (b) on the basis of long experience with the method, it is believed that s --> o = 0.26% lindane Confidence interval = ± % lindane

Appl Of Ms Excel In Analytical Chemistry

2nd Edition

ISBN:9781285686691

Author:Crouch

Publisher:Crouch

Chapter2: Basic Statistical Analysis With Excel

Section: Chapter Questions

Problem 12P

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A chemist obtained the following data for percent lindane in the triplicate analysis of an insecticide preparation: 7.23, 6.95, and 7.53%. Calculate the 90% confidence interval for the mean of the the three data, assuming that (a) the only information about the precision of the method is the precision for the three data. (b) on the basis of long experience with the method, it is believed that s---->σ lindane. (c) If s=0.28 is good estimate of σ, how many replicate measurement should be made in order for the mean for the analysis of sample to be within 0.2% of the true mean 90% of the time.
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