To measure the iron content of runoff from a ranch a 25.0 mL sample of run off was acidified with HNO3 and treated with excess KSCN to form a red complex. (KSCN itself is colorless.) The solution was then diluted to 100 mL and put into a variable pathlenght cell. For comparison, a 10.0 mL reference sample of 6.80 x 10-4 M Fe3+ was treated with HNO3 and KSCN and diluted to 50.0 mL. The reference was placed in a cell with a 1.00 cm pathlenght. The runoff had the same absorbance as the reference when the pathlenght of the runoff cell was 2.48 cm. What wa the concentraton of iron in the runoff?

To measure the iron content of runoff from a ranch a 25.0 mL sample of run off was acidified with HNO3 and treated with excess KSCN to form a red complex. (KSCN itself is colorless.) The solution was then diluted to 100 mL and put into a variable pathlenght cell. For comparison, a 10.0 mL reference sample of 6.80 x 10-4 M Fe3+ was treated with HNO3 and KSCN and diluted to 50.0 mL. The reference was placed in a cell with a 1.00 cm pathlenght. The runoff had the same absorbance as the reference when the pathlenght of the runoff cell was 2.48 cm. What wa the concentraton of iron in the runoff?

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter26: Molecular Absorption Spectrometry

Section: Chapter Questions

Problem 26.12QAP

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When I was a boy, I watched Uncle Wilbur measure the iron content of runoff from his banana ranch. He acidified a 25.0-mL sample with HNO3 and treated it with excess KSCN to form a red complex. (KSCN itself is colorless.) He then diluted the solution to 100.0 mL and put it in a variablepathlength cell. For comparison, he treated a 10.0-mL reference sample of 6.80X 1024 M Fe31 with HNO3 and KSCN and diluted it to 50.0 mL. The reference was placed in a cell with a 1.00-cm pathlength. Runoff had the same absorbance as the reference when the pathlength of the runoff cell was 2.48 cm. What was the concentration of iron in Uncle Wilbur’s runoff ?
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