10-mL aliquots of an environmental water sample were pipetted into five 50.00-mL volumetric flasks. Exactly 0.00, 5.00, 10.00, 15.00, and 20.00-mL of a standard solution containing 11.1 ppm Fe3+ were added to each, followed by an excess of thiocyanate ion to give the red complex Fe(SCN)2+. After dilution to volume, the instrumental response for each of the five solutions measured with a colorimeter was found to be 0.240, 0.437, 0.621, 0.809, 1.809, respectively. Using Excel and the LINEST function, what was the concentration in the water sample (including error)? [HINT: consider the type of calibration scheme used.]

10-mL aliquots of an environmental water sample were pipetted into five 50.00-mL volumetric flasks. Exactly 0.00, 5.00, 10.00, 15.00, and 20.00-mL of a standard solution containing 11.1 ppm Fe3+ were added to each, followed by an excess of thiocyanate ion to give the red complex Fe(SCN)2+. After dilution to volume, the instrumental response for each of the five solutions measured with a colorimeter was found to be 0.240, 0.437, 0.621, 0.809, 1.809, respectively. Using Excel and the LINEST function, what was the concentration in the water sample (including error)? [HINT: consider the type of calibration scheme used.]

Chemistry: Principles and Reactions

8th Edition

ISBN:9781305079373

Author:William L. Masterton, Cecile N. Hurley

Publisher:William L. Masterton, Cecile N. Hurley

Chapter15: Complex Ion And Precipitation Equilibria

Section: Chapter Questions

Problem 68QAP

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