Water from Jordan Lake was analyzed for its Fe³+ content. A 20.0-mL sample of lake water was acidified with nitric acid and treated with excess KSCN to form a red complex (KSCN itself is colorless). The solution was then diluted to 50.0-mL and put in a 1.00 cm pathlength cell, where it yielded an absorbance of 0.345. For comparison, a 5.0-mL reference sample of 4.80 x 10 4 M Fe³+ was treated with HNO3 and KSCN and diluted to 50.0 mL. The reference solution was also placed in a 1.00-cm cell and gave an absorbance of 0.512. What is the concentration of Fe³+ in Jordan Lake? A. 9.16 x 10-4 M B. 4.58 x 10-5 M C. 6.80 x 10-5 M D. 2.29 x 10-5 M E. 1.14 x 10-4 M F. 8.09 x 10-5 M G. 1.77 x 10-4 M OH. 8.46 x 10-4 M

Water from Jordan Lake was analyzed for its Fe³+ content. A 20.0-mL sample of lake water was acidified with nitric acid and treated with excess KSCN to form a red complex (KSCN itself is colorless). The solution was then diluted to 50.0-mL and put in a 1.00 cm pathlength cell, where it yielded an absorbance of 0.345. For comparison, a 5.0-mL reference sample of 4.80 x 10 4 M Fe³+ was treated with HNO3 and KSCN and diluted to 50.0 mL. The reference solution was also placed in a 1.00-cm cell and gave an absorbance of 0.512. What is the concentration of Fe³+ in Jordan Lake? A. 9.16 x 10-4 M B. 4.58 x 10-5 M C. 6.80 x 10-5 M D. 2.29 x 10-5 M E. 1.14 x 10-4 M F. 8.09 x 10-5 M G. 1.77 x 10-4 M OH. 8.46 x 10-4 M

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter17: Complexation And Precipitation Reactions And Titrations

Section: Chapter Questions

Problem 17.31QAP

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