STUDENT NAME N I CO/45 Nieves D. Real World Examples Example 1 In a lab a chemist needs to identify which metal cation is in an unknown toxic waste 3+ sample. On a piece of chromatography paper he spots solutions of Cu?*, Ni² and Fe" and his unknown. He uses a developing solution of a mixture of HCI, water and 2+ acetone. What are the Rf values for each cation sample? Rf Distance traveled Show calc. Solvent front 14.5 cm distance Cu²+ 5.5 cm :2+ 11.8 cm Fe * 8.0 cm Unknown 11.1 cm What is the likely identity of the unknown? Briefly explain your answer. Example 2 chemist is running a forensic laboratory. Using the Rf values in the table below, ermine which solvent she would use to analyze a sample seized by the police in a g smuggling case. Explain your answer. Drug Cocaine Methamphetamine Acetone/water Water/denatured alcohol Vinegar/acetone 0.11 0.14 0.42 0.71 0.76 0.45 Morphine *Note: though the example is reasonable, the data is concocted. 0.72 0.82 0.75

STUDENT NAME N I CO/45 Nieves D. Real World Examples Example 1 In a lab a chemist needs to identify which metal cation is in an unknown toxic waste 3+ sample. On a piece of chromatography paper he spots solutions of Cu?, Ni² and Fe" and his unknown. He uses a developing solution of a mixture of HCI, water and 2+ acetone. What are the Rf values for each cation sample? Rf Distance traveled Show calc. Solvent front 14.5 cm distance Cu²+ 5.5 cm :2+ 11.8 cm Fe 8.0 cm Unknown 11.1 cm What is the likely identity of the unknown? Briefly explain your answer. Example 2 chemist is running a forensic laboratory. Using the Rf values in the table below, ermine which solvent she would use to analyze a sample seized by the police in a g smuggling case. Explain your answer. Drug Cocaine Methamphetamine Acetone/water Water/denatured alcohol Vinegar/acetone 0.11 0.14 0.42 0.71 0.76 0.45 Morphine *Note: though the example is reasonable, the data is concocted. 0.72 0.82 0.75

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

ChapterA1: Evaluation Of Analytical Data

Section: Chapter Questions

Problem A1.24QAP

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