It was decided to analyze a waste solution that contains an unknown concentration of Mn²* ions using colorimetry. A strong oxidizing agent was added to a 6.40 ml sample of the solution to convert the colorless manganese ions into purple permanganate ions. After the reaction is complete, the solution was diluted to 250.0 mlL and analyzed in a colorimeter. The percent transmittance of the solution was determined to be 46.0%. Also a calibration curve was prepared by using a series of solutions with known concentrations of permanganate and the equation for the best fit line was found. y = 1910 - x + 0.035 What is the absorbance of the permanganate in the diluted waste solution? A = What is the concentration of the permanganate in the diluted waste solution? concentration: M What is the concentration of the Mn²+ ions in the original waste solution? [Mn *] =

It was decided to analyze a waste solution that contains an unknown concentration of Mn²* ions using colorimetry. A strong oxidizing agent was added to a 6.40 ml sample of the solution to convert the colorless manganese ions into purple permanganate ions. After the reaction is complete, the solution was diluted to 250.0 mlL and analyzed in a colorimeter. The percent transmittance of the solution was determined to be 46.0%. Also a calibration curve was prepared by using a series of solutions with known concentrations of permanganate and the equation for the best fit line was found. y = 1910 - x + 0.035 What is the absorbance of the permanganate in the diluted waste solution? A = What is the concentration of the permanganate in the diluted waste solution? concentration: M What is the concentration of the Mn²+ ions in the original waste solution? [Mn *] =

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

Chapter27: Gas Chromatography

Section: Chapter Questions

Problem 27.5QAP

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In an analysis of chromium in steel containing 1.76% Cr. 0.5000 g of that steel is weighed and dissolved in acid, whereupon the Cr is oxidized to Cr2O72- (dichromate), and blunt to a volume of 250 mL. A 10 mL aliquot of this solution is diluted with water and acid to a final volume of 100 mL. The resulting solution shows a transmittance of 41.7% in a 1 cm pathlength cell. When a 0.7500 g sample of unknown steel is dissolved in acid, oxidized, and diluted to 250 mL, the resulting solution exhibits a transmittance of 61.3% under identical experimental conditions. What is the percentage of Cr in the steel?
You are given two containers, one with 3.00 mg Mn 2+ and one with an unknown amount of Mn 2+ .You oxidize the Mn 2+ to the purple permanganate ion (MnO 4 - ) and dilute the solutions to 250.0 mLs.The solution containing the 3.00 mg Mn is used to prepare a third solution containing 1.50 mg Mn.The transmittances of the solutions are measured at 530 nm using a dilapidated Spectronic 20. Fromthe data below, calculate the amount of Mn in the unknown. For a linear curve, consider y=kx+b Mn (mg) %T3.00 30.81.50 55.2Unknown 37.4
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