The determination of copper in a sca water sample gave a mean value of 77.81 ug/L and a standard deviation, s of 1.74 ug/L. How many samples must be analysed to obtain a relative standard deviation of 1.7% in the results at the 95% confidence level?

The determination of copper in a sca water sample gave a mean value of 77.81 ug/L and a standard deviation, s of 1.74 ug/L. How many samples must be analysed to obtain a relative standard deviation of 1.7% in the results at the 95% confidence level?

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter8: Sampling, Standardization, And Calibration

Section: Chapter Questions

Problem 8.13QAP

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