SPECTROPHOTОМЕ TRYThe DPD colorimetric method is used to determine the amount of residual chlorine in thesample. In this method, the free chlorine in the sample oxidizes the colorless amine N,N-diethyl-p-phenylenediamine to a colored compound that absorbs strongly at 520 nm. Theanalysis of a set of calibration standards gave the following results:Absorbance0.00310.12320.3241ppm Cl20.000.501.001.500.54382.000.76422.500.95513.001.1565A 10.00 mL water sample from a public water supply was diluted to 250 mL and analyzedfor free chlorine residual, giving an absorbance of 0.3210.A. Find the equation of the line.B. What is the molar absorptivity of Cl2 (FW = 70.9) at 250 nm?C. Calculate the free chlorine residual of the sample as ppm Cl2.D. Calculate ppm BaCl2 (FW = 208.2)?

SPECTROPHOTOME TRY The DPD colorimetric method is used to determine the amount of residual chlorine in the sample. In this method, the free chlorine in the sample oxidizes the colorless amine N,N- diethyl-p-phenylenediamine to a colored compound that absorbs strongly at 520 nm. The analysis of a set of calibration standards gave the following results: ppm Cl2 0.00 0.50 1.00 1.50 2.00 2.50 3.00 Absorbance 0.0031 0.1232 0.3241 0.5438 0.7642 0.9551 1.1565 A 10.00 mL water sample from a public water supply was diluted to 250 mL and analyzed for free chlorine residual, giving an absorbance of 0.3210. A. Find the equation of the line. B. What is the molar absorptivity of Cl2 (FW = 70.9) at 250 nm? C. Calculate the free chlorine residual of the sample as ppm Cl2. D. Calculate ppm BaCl2 (FW = 208.2)?

SPECTROPHOTOME TRY The DPD colorimetric method is used to determine the amount of residual chlorine in the sample. In this method, the free chlorine in the sample oxidizes the colorless amine N,N- diethyl-p-phenylenediamine to a colored compound that absorbs strongly at 520 nm. The analysis of a set of calibration standards gave the following results: ppm Cl2 0.00 0.50 1.00 1.50 2.00 2.50 3.00 Absorbance 0.0031 0.1232 0.3241 0.5438 0.7642 0.9551 1.1565 A 10.00 mL water sample from a public water supply was diluted to 250 mL and analyzed for free chlorine residual, giving an absorbance of 0.3210. A. Find the equation of the line. B. What is the molar absorptivity of Cl2 (FW = 70.9) at 250 nm? C. Calculate the free chlorine residual of the sample as ppm Cl2. D. Calculate ppm BaCl2 (FW = 208.2)?

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

Chapter1: Introduction

Section: Chapter Questions

Problem 1.11QAP

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The DPD colorimetric method is used to determine the amount of residual chlorine in the sample. In this method, the free chlorine in the sample oxidizes the colorless amine N,N-diethyl-p-phenylenediamine to a colored compound that absorbs strongly at 520 nm. The analysis of a set of calibration standards gave the following results:ppm Cl2 Absorbance0.00 0.00310.50 0.12321.00 0.32411.50 0.54382.00 0.76422.50 0.95513.00 1.1565A 10.00 mL water sample from a public water supply was diluted to 250 mL and analyzed for free chlorine residual, giving an absorbance of 0.3210.A. Find the equation of the line.B. What is the molar absorptivity of Cl2 (FW = 70.9) at 250 nm?C. Calculate the free chlorine residual of the sample as ppm Cl2.D. Calculate ppm BaCl2 (FW = 208.2)?
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