The following volumes of a solution containing 1.10 ppm Zn2+ were pipetted into separatory funnels each containing 5.00 mL of an unknown zinc solution: 0.00, 1.00, 4.00, 8.00 and 12.00. Each was extracted with three 5 mL aliquots of CCl4 containing an excess of 8-hydroxyquinoline. The extracts were then diluted to 25.0 mL and their fluorescence measured with a fluorometer. The results for the standard addition calibration were as follows: Volume Std. Zn2+ / mL [Zn2+] / ppm Fluorometer Reading 0.00 6.12 1.00 7.41 4.00 11.16 8.00 15.68 12 20.64 a) Determine the concentration on Zn2+ ions in each of the standard solutions coming from the coming from the 1.10 ppm Zn2+ solutions, Please show your working

The following volumes of a solution containing 1.10 ppm Zn2+ were pipetted into separatory funnels each containing 5.00 mL of an unknown zinc solution: 0.00, 1.00, 4.00, 8.00 and 12.00. Each was extracted with three 5 mL aliquots of CCl4 containing an excess of 8-hydroxyquinoline. The extracts were then diluted to 25.0 mL and their fluorescence measured with a fluorometer. The results for the standard addition calibration were as follows: Volume Std. Zn2+ / mL [Zn2+] / ppm Fluorometer Reading 0.00 6.12 1.00 7.41 4.00 11.16 8.00 15.68 12 20.64 a) Determine the concentration on Zn2+ ions in each of the standard solutions coming from the coming from the 1.10 ppm Zn2+ solutions, Please show your working

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

Chapter15: Molecular Luminescence Spectrometry

Section: Chapter Questions

Problem 15.8QAP

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