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 = 0.01402 x - 0.1300 B) y = -0.1700 x + 0.01402 y = -0.1300 x + 0.01402 D y = 0.01402 x -0.1700

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 = 0.01402 x - 0.1300 B) y = -0.1700 x + 0.01402 y = -0.1300 x + 0.01402 D y = 0.01402 x -0.1700

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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