A dual beam UV-visible spectroscopy was used to determine the levels of Fe(II) in the run-off water of a local mine using the ferrozine assay (i) During a check of the instrument a step-like feature at 360 nm was observed in spectrum of the standard. Suggest what may give rise to this with reference to the instrument configuration and comment on how it may be remedied. (ii) The molar absorptivity of the [Fe(Ferrozine)3]2+ complex is 27900 cm−1 M−1 at 562 nm in aqueous solution (pH 5.5). If the EU maximum contaminant level for Fe is 200 ug /L and the contract required detection limit is 100 ug/L, comment on the suitability of the assay for the detection of iron. (iii) Determine the sample range, in terms of concentration and ppm, of Fe(II) that can be confidently analysed by UV-visible spectroscopy using a 1 cm cuvette. Explain with reference to an appropriate equation and solution phenomena, the origin of the limitations that define this range

A dual beam UV-visible spectroscopy was used to determine the levels of Fe(II) in the run-off water of a local mine using the ferrozine assay (i) During a check of the instrument a step-like feature at 360 nm was observed in spectrum of the standard. Suggest what may give rise to this with reference to the instrument configuration and comment on how it may be remedied. (ii) The molar absorptivity of the [Fe(Ferrozine)3]2+ complex is 27900 cm−1 M−1 at 562 nm in aqueous solution (pH 5.5). If the EU maximum contaminant level for Fe is 200 ug /L and the contract required detection limit is 100 ug/L, comment on the suitability of the assay for the detection of iron. (iii) Determine the sample range, in terms of concentration and ppm, of Fe(II) that can be confidently analysed by UV-visible spectroscopy using a 1 cm cuvette. Explain with reference to an appropriate equation and solution phenomena, the origin of the limitations that define this range

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

Chapter9: Atomic Absorption And Atomic Fluorescence Spectrometry

Section: Chapter Questions

Problem 9.23QAP

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