A quantitative spectrophotometric procedure for iron based on a solid phase extraction using bathophenanthroline in a poly(vinyl chloride) membrane is described. In the absence of Fe2+ the membrane is colorless, but when immersed in a solution of Fe2+ and I, the membrane develops a red color as a result of the formation of an Fe2+_ bathophenanthroline complex. A calibration curve determined using a set of external standards with known concentrations of Fe²+ standardization relationship of gave a A=(8.60×10 M )×[Fe] What is the concentration of iron, in ppm, for a sample with an absorbance of 0.100.

A quantitative spectrophotometric procedure for iron based on a solid phase extraction using bathophenanthroline in a poly(vinyl chloride) membrane is described. In the absence of Fe2+ the membrane is colorless, but when immersed in a solution of Fe2+ and I, the membrane develops a red color as a result of the formation of an Fe2+_ bathophenanthroline complex. A calibration curve determined using a set of external standards with known concentrations of Fe²+ standardization relationship of gave a A=(8.60×10 M )×[Fe] What is the concentration of iron, in ppm, for a sample with an absorbance of 0.100.

Principles of Instrumental Analysis

7th Edition

ISBN:9781305577213

Author:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Publisher:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Chapter14: Applications Of Ultraviolet-visible Molecular Absorption Spectrometry

Section: Chapter Questions

Problem 14.19QAP

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The accompanying data (1.00-cm cells) were obtained for the spectrophotometric titration 10.00 mL of Pd(II) with 2.44 10-4 M Nitroso R(O. W Rollins and M. M. Oldham, Anal. chem .,1971, 43, 262, DOI: 10.1021/ac60297a026). Calculate the concentration of the Pd(II) solution, given that the ligand-to-cation ratio in the colored product is 2:1
A 25.00 mL sample containing Fe3+ was treated with 10.00 mL of 0.03676 M EDTA to complex all the Fe3+ and leave excess EDTA in solution. The excess EDTA was then back-titrated, requiring 2.37 mL of 0.04615 M Mg2+. What was the concentration of Fe3+ in the original solution in ppm Fe3+?
A 50.0 mL sample containing Cd²+ and Mn²+ was treated with 57.3 mL of 0.0700 M EDTA. Titration of the excess unreacted EDTA required 16.1 mL of 0.0250 M Ca²+. The Cd²+ was displaced from EDTA by the addition of an excess of CN¯. Titration of the newly freed EDTA required 25.5 mL of 0.0250 M Ca²+. What are the concentrations of Cd²+ and Mn²+ in the original solution? concentration: concentration: 2+ M Mn2 MCd2+
A 50.0-mL sample containing Ni2+ was treated with 25.0 mL of 0.0500 M EDTA to complex all the Ni2+ and leave excess EDTA in solution. The excess EDTA was then back-titrated, requiring 5.00 mL of 0.0500 M Zn2+. What was the molar concentration of Ni2+ in the original solution?
A 50.0 mL sample containing Cd²+ and Mn2+ was treated with 60.9 mL of 0.0700 M EDTA. Titration of the excess unreacted EDTA required 18.9 mL of 0.0220 M Ca2+. The Cd2+ was displaced from EDTA by the addition of an excess of CN-. Titration of the newly freed EDTA required 16.3 mL of 0.0220 M Ca+. What are the concentrations of Cd2+ and Mn2+ in the original solution? concentration: М Mn2+ concentration: M Cd²+
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tion 13 of 24 > The standard curve was made by spectrophotographic analysis of equilibrated iron(III) thiocyanate solutions of known concentration. You are asked to analyze a Fe(SCN)²+ solution with an unknown concentration and an absorbance value of 0.179. The slope-intercept form of the equation of the line is y = 4536.6x + 0.0392. The unknown was analyzed on the same %3D instrument as the standard curve solutions at the same temperature. What is the Fe3+ concentration of the unknown solution? Iron(III) thiocynate standard curve 1.0 - Fe*] = mol/L 0.5- 0.0001 0.0002 Fe+ concentration (M) Absorbance
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