One of the challenges in creating new laboratory materials is developing activities that embrace the required complex topics while engaging the students through the utilization of real-world examples. At Concordia College in Minnesota, we have worked on improving student understanding of polarity and chromatography in the general chemistry laboratory through a series of new laboratory activities. Our project incorporated commercially available colored materials, namely marker pens and food dyes, which possess components of differing polarities that the students were able to separate out using different methods of chromatography. The colorful nature and minimal hazardous waste of the food dyes make them ideal for these brand new, engaging labs. Students in the class carried out activities showing the principles of chromatography and the results of varying polarity of mobile and stationary phase in a series of thin-layer chromatography experiments. The fundamentals gained here were further developed in looking at analysis of commercial food dyes in materials such as commercial food colors and candies by HPLC. These experiments were successfully implemented at Concordia College in the fall of 2019 and in modified (due to COVID-19) in-person form in Fall 2020. Students surveyed before and after the experiments showed improvement in their knowledge of polarity and their attitude towards that subject matter in both years.<br/><br/>The development of these experiments was made possible by the Centennial Scholars Classroom Research grant from Concordia College and the generous donation of the HPLC by Analytical Instruments, Minnesota.

From thin-layer to high performance: Introducing chromatography and polarity to the first semester general chemistry laboratory

ACS Spring Meeting 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.