A student researcher measured the cadmium (C*) content in a standard reference material (SRM) using graphite furnace atomic absorption spectrometry (GFAAS). With 7 replicate measurements, the researcher determined a mean Cd+ concentration of 3.127 ppb with a standard deviation of 0.006 ppb. Calculate the 98% confidence interval for this sample. A list of i values can be found in the Student's 1 table. 3.127 ppbt ppb

A student researcher measured the cadmium (C*) content in a standard reference material (SRM) using graphite furnace atomic absorption spectrometry (GFAAS). With 7 replicate measurements, the researcher determined a mean Cd+ concentration of 3.127 ppb with a standard deviation of 0.006 ppb. Calculate the 98% confidence interval for this sample. A list of i values can be found in the Student's 1 table. 3.127 ppbt ppb

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter16: Applications Of Neutralization Titrations

Section: Chapter Questions

Problem 16.18QAP

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A titrimetric method for the determination of calcium in limestone was tested by analysis of an NIST limestone containing 30.15% CaO. The mean result of four analyses was 30.26% CaO, with a standard deviation of 0.085%. By pooling data from several analyses, it was established that s   = 0.094% CaO.a. Do the data indicate the presence of a systematic error at the 95% confidence level?b. Do the data indicate the presence of systematic error at the 95% confidence level if no pooled value for s was available?
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