Potassium dichromate (K2Cr2O7) and potassium permanganate (KMNO4) give overlapping UV-Vis absorption spectra in 1 M şulphuric acid. K.CrO; shows an absorption maximum at 440 nm and KMNO4 shows the absorption maximum at 545 nm. An unknown sample solution containing a mixture of K;Cr2O7 and KMNO4 was analyzed using a 1-cm cell and the absorbance values at these two wavelengths were as follows: b. A440 = 0.515 and A$45 = 0.835 The absorbance values for standard solutions of K:Cr2O; (1.00 x 10³ M) and KMNO: (2.00 x 104 M) in 1 M sulphuric acid using the same 1 cm cell were as follows: | Absorbance, A | Absorbance, A 440 nm 545 nm 0.374 0.009 KMNO4 0.019 0.475 Calculate the concentrations of K2CrO7 and KMNO4 in the unknown sample.

Potassium dichromate (K2Cr2O7) and potassium permanganate (KMNO4) give overlapping UV-Vis absorption spectra in 1 M şulphuric acid. K.CrO; shows an absorption maximum at 440 nm and KMNO4 shows the absorption maximum at 545 nm. An unknown sample solution containing a mixture of K;Cr2O7 and KMNO4 was analyzed using a 1-cm cell and the absorbance values at these two wavelengths were as follows: b. A440 = 0.515 and A$45 = 0.835 The absorbance values for standard solutions of K:Cr2O; (1.00 x 10³ M) and KMNO: (2.00 x 104 M) in 1 M sulphuric acid using the same 1 cm cell were as follows: | Absorbance, A | Absorbance, A 440 nm 545 nm 0.374 0.009 KMNO4 0.019 0.475 Calculate the concentrations of K2CrO7 and KMNO4 in the unknown sample.

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 14.9QAP

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