d) The following data was obtained from the determination of lead, Pb in a wastewater sample. Four measurements were made. The set of data obtained was as follow: Measurement 1 2 3 4 3 14.1 15.2 14.9 15.4 Pb concentration (ppm) i) Using Q-test, justify whether the outlier should be rejected or accepted at 90% confidence level. ii) Calculate the mean and standard deviation of the data set after the Q-test has been done. iii) Determine the 90% confidence limit for the true concentration of Pb in the sample.

d) The following data was obtained from the determination of lead, Pb in a wastewater sample. Four measurements were made. The set of data obtained was as follow: Measurement 1 2 3 4 3 14.1 15.2 14.9 15.4 Pb concentration (ppm) i) Using Q-test, justify whether the outlier should be rejected or accepted at 90% confidence level. ii) Calculate the mean and standard deviation of the data set after the Q-test has been done. iii) Determine the 90% confidence limit for the true concentration of Pb in the sample.

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter7: Statistical Data Treatment And Evaluation

Section: Chapter Questions

Problem 7.13QAP

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