Appl Of Ms Excel In Analytical Chemistry
2nd Edition
ISBN: 9781285686691
Author: Crouch
Publisher: Cengage
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A titrimetric method for the determination of calcium in limestone was tested with the analysis of a NIST limestone containing 30.15% CaO. The mean of the four analyzes is 30.26% CaO with a standard deviation of 0.085%. From the data accumulated from many analyzes, s→ϭ=0.094% CaO was found.a) Do the data indicate the presence of systematic error at the 95% confidence level?b) When a value for ϭ is unknown, do the data show a systematic error at the 95% confidence level?
In replicate analyses, the carbohydrate content of a glycoprotein (a
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and 12.5 g of carbohydrate per 100 g of protein.
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(c) Find the 90% confidence intervals for the carbohydrate content.
(d) If the mean and s are unchanged, but there are 10 measurements
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(e) How does increasing the number of replicate measurements
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