A set of three replicate AAS measurements were made from the same calcium standard. Use the information below to determine the LOD for calcium analysis. ⚫ The standard was prepared by dissolving 0.020 g of CaCO, in acid and diluting to 1.000 L. ⚫ After blanking the instrument, the three absorbance readings from the standard were 0.101, 0.096, and 0.104. Hint: Determine the slope of a 'two-point' calibration plot using the blank and average reading of the standard; use the standard deviation of the 3 absorbance readings as s ( )4 ppm ( )3 ppm ( ) 1 ppm ( ) 0.2 ppm

A set of three replicate AAS measurements were made from the same calcium standard. Use the information below to determine the LOD for calcium analysis. ⚫ The standard was prepared by dissolving 0.020 g of CaCO, in acid and diluting to 1.000 L. ⚫ After blanking the instrument, the three absorbance readings from the standard were 0.101, 0.096, and 0.104. Hint: Determine the slope of a 'two-point' calibration plot using the blank and average reading of the standard; use the standard deviation of the 3 absorbance readings as s ( )4 ppm ( )3 ppm ( ) 1 ppm ( ) 0.2 ppm

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter31: Introduction To Analytical Separations

Section: Chapter Questions

Problem 31.1QAP

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