Resumen de Analytical Problems Associated with the Analysis of Metals in a Simulated Hazardous Waste
Analysis of samples subject to physical and chemical interferences can greatly enhance the learning experience in instrumental analysis and environmental chemistry laboratories. This article describes a project-based experience in which students analyze simulated hazardous waste samples (carbonated beverages) for calcium by six techniques: (i) flame atomic absorption spectroscopy (FAAS) using external standard calibration, (ii) FAAS using external standard calibration with a releasing agent (Sr), (iii) FAAS using standard addition, (iv) FAAS using standard addition with a releasing agent (Sr), (v) ethylenediaminetetraacetic acid (EDTA) titration, and (vi) Ca-ion-specific electrode. Not surprisingly, students find that these different techniques yield conflicting results and their assignment is to explain their data in the format of a peer-reviewed journal article. Students report that this series of lab experiments is challenging and highly rewarding. Laboratory experiences such as this one should significantly improve the student's ability to analyze problematic samples and interpret experimental data.
