A standard solution was put through appropriate dilu tions to give the concentrationsof iron shown in the ac companying table. The iron(II)-1,10,phenanthroline complexwas then formed in 25.0-ml aliquots of these solutions, following which each wasdiluted to 50.0 mL (see color plate 15). The absorbances in the table (1.00-cm cells)were recorded at 510 nmFe(II) Concentration inOriginal Solution, ppmAşie4.000.1600.39010.016.00.63024.00.95032.01.26040.01.580(a) Plot a calibration curve from these data.(b) Use the method of least squares to find an equa tion relatin g absorbance and theconcentration of iron(II).(c) Calculate the standard deviation of the slope and intercept.

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A standard solution was put through appropriate dilu tions to give the concentrations of iron shown in the ac companying table. The iron(II)-1,10,phenanthroline complex was then formed in 25.0-mL aliquots of these solutions, following which each was dluted to 50.0 mL (see color plate 15). The absorbances in the table (1.00-cm cells) vere recorded at 510 nm Fe(II) Concentration in Original Solution, Ppm 4.00 0.160 10.0 16.0 24.0 0.390 0.630 0.950 32.0 1.260 40.0 1.580 a) Plot a calibration curve from these data. b) Use the method of least squares to find an equa tion relating absorbance and the concentration of iron(II). c) Calculate the standard deviati on of the slope and intercept.

A standard solution was put through appropriate dilu tions to give the concentrations of iron shown in the ac companying table. The iron(II)-1,10,phenanthroline complex was then formed in 25.0-mL aliquots of these solutions, following which each was dluted to 50.0 mL (see color plate 15). The absorbances in the table (1.00-cm cells) vere recorded at 510 nm Fe(II) Concentration in Original Solution, Ppm 4.00 0.160 10.0 16.0 24.0 0.390 0.630 0.950 32.0 1.260 40.0 1.580 a) Plot a calibration curve from these data. b) Use the method of least squares to find an equa tion relating absorbance and the concentration of iron(II). c) Calculate the standard deviati on of the slope and intercept.

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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