Vanadium forms a complex with peroxide which absorbs at 460 nm. A 3.96 × 10 -4M solution of vanadium peroxide (Solutic A) exhibited an absorbance of 0.624 at 460 nm in a 1.000-cm quartz cuvette; a blank solution containing only solvent had an absorbance of 0.029 at the same wavelength. a) Find the molar absorptivity of vanadium peroxide complex. b) An unknown solution of vanadium peroxide complex in the same solvent and cuvette had an absorbance of 0.375 at 46 nm. Find the concentration of vanadium peroxide in the unknown solution. c) A concentrated solution vanadium peroxide in the same solvent was diluted from an initial volume of 5.00 mL to a final volume of 25.00 mL (Solution C) had an absorbance of 0.733 in the same cuvette. What is the concentration of vanadium peroxide in the concentrated solution (Solution B)? Answer the following questions: 1. Molar Absorptivity (Mª cm ?) of vanadium peroxide complex from Solution A at 460 nm 2. Concentration of vanadium peroxide in unknown solution in mmole/L 3. Concentration of vanadium peroxide in solution C in mmole/L 4. Concentration of vanadium peroxide in concentrated solution (Solution B) in mmole/L

Vanadium forms a complex with peroxide which absorbs at 460 nm. A 3.96 × 10 -4M solution of vanadium peroxide (Solutic A) exhibited an absorbance of 0.624 at 460 nm in a 1.000-cm quartz cuvette; a blank solution containing only solvent had an absorbance of 0.029 at the same wavelength. a) Find the molar absorptivity of vanadium peroxide complex. b) An unknown solution of vanadium peroxide complex in the same solvent and cuvette had an absorbance of 0.375 at 46 nm. Find the concentration of vanadium peroxide in the unknown solution. c) A concentrated solution vanadium peroxide in the same solvent was diluted from an initial volume of 5.00 mL to a final volume of 25.00 mL (Solution C) had an absorbance of 0.733 in the same cuvette. What is the concentration of vanadium peroxide in the concentrated solution (Solution B)? Answer the following questions: 1. Molar Absorptivity (Mª cm ?) of vanadium peroxide complex from Solution A at 460 nm 2. Concentration of vanadium peroxide in unknown solution in mmole/L 3. Concentration of vanadium peroxide in solution C in mmole/L 4. Concentration of vanadium peroxide in concentrated solution (Solution B) in mmole/L

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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