A sample was analysed for its Calcium concentration. A number of standard solutions were prepared (ppm) and their absorbance values were determined. The results were plotted in Excel (concentration on x-axis and absorbance on y-axis) and the following equation for the best fit line was obtained. y = 3.149 x + 0.222. The absorbance of the unknown sample was measures as 8,66. What is the concentration of the unknown sample? Answer to 2 decimal places. a) 8.56 ppm b) 2.75 ppm с) 1.66 рpm d) 2.68 ppm

A sample was analysed for its Calcium concentration. A number of standard solutions were prepared (ppm) and their absorbance values were determined. The results were plotted in Excel (concentration on x-axis and absorbance on y-axis) and the following equation for the best fit line was obtained. y = 3.149 x + 0.222. The absorbance of the unknown sample was measures as 8,66. What is the concentration of the unknown sample? Answer to 2 decimal places. a) 8.56 ppm b) 2.75 ppm с) 1.66 рpm d) 2.68 ppm

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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