A sample of body serum is to be analysed for sodium by flame emission spectroscopy. 1.00cm' aliquot of serum was pipetted into each of two 50.0cm' volumetric flasks. The first flask was diluted to volume with deionised water. The absorbance of this first solution was0.350. To the second flask 10.0 cm' of a 25.0 ppm sodium standard was added and the flask made up to volume with deionised water. The absorbance of this second solution was 0.720.(i) Calculate the concentration of the sodium in the body serum in mg dm-3.

A sample of body serum is to be analysed for sodium by flame emission spectroscopy. 1.00cm' aliquot of serum was pipetted into each of two 50.0cm' volumetric flasks. The first flask was diluted to volume with deionised water. The absorbance of this first solution was0.350. To the second flask 10.0 cm' of a 25.0 ppm sodium standard was added and the flask made up to volume with deionised water. The absorbance of this second solution was 0.720.(i) Calculate the concentration of the sodium in the body serum in mg dm-3.

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter26: Molecular Absorption Spectrometry

Section: Chapter Questions

Problem 26.32QAP

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(a) A sample of body serum is to be analysed for sodium by flame emission spectroscopy. 1.00cm3 aliquot of serum was pipetted into each of two 50.0 cm3 volumetric flasks. The firstflask was diluted to volume with deionised water. The absorbance of this first solution was0.350. To the second flask 10.0 cm3 of a 25.0 ppm sodium standard was added and theflask made up to volume with deionised water. The absorbance of this second solution was0.720.(i) Calculate the concentration of the sodium in the body serum in mg dm–3
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