Calibrations, Standardizations, and Blank Corrections

 Calibrations, Standardizations, and Blank Corrections

We introduced a relationship between the measured signal,Smeas, and the absolute amount of analyte

Smeas = knA + Sreag      ……… 5.1

or the relative amount of analyte in a sample

Smeas = kCA + Sreag     ……… 5.2

where nA is the moles of analyte, CA is the analyte’s concentration, k is the method’s sensitivity, and Sreag is the contribution to Smeas from constant errors introduced by the reagents used in the analysis. To obtain an accurate value for nA or CA it is necessary to avoid determinate errors affecting Smeas, k, and Sreag. This is accomplished by a combination of calibrations, standardizations, and reagent blanks.

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