A chemist prepared a reagent blank and 6 Fe standards with the following concentrations: 20, 30, 40, 50, 60, and 70 ppm. The table below shows the average reading of each run in the UV-Vis spectrophotometer. Concentration (ppm)- --Absorbance (au) 20-- -0.121 30- -0.302 40- -0.468 50- -0.573 60- -0.696 70- -0.845 Blank- -0.04 Which of the following is the correct equation for the calibration curve? A) y = -0.1700 x + 0.01402 B) y = 0.01402 x - 0.1700 (C) y = -0.1300 x + 0.01402 (D) y = 0.01402 x - 0.1300

A chemist prepared a reagent blank and 6 Fe standards with the following concentrations: 20, 30, 40, 50, 60, and 70 ppm. The table below shows the average reading of each run in the UV-Vis spectrophotometer. Concentration (ppm)- --Absorbance (au) 20-- -0.121 30- -0.302 40- -0.468 50- -0.573 60- -0.696 70- -0.845 Blank- -0.04 Which of the following is the correct equation for the calibration curve? A) y = -0.1700 x + 0.01402 B) y = 0.01402 x - 0.1700 (C) y = -0.1300 x + 0.01402 (D) y = 0.01402 x - 0.1300

Appl Of Ms Excel In Analytical Chemistry

2nd Edition

ISBN:9781285686691

Author:Crouch

Publisher:Crouch

Chapter12: Spectrochemical Methods

Section: Chapter Questions

Problem 10P

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