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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