Examination of Bond Properties through Infrared Spectroscopy and Molecular Modeling in the General Chemistry Laboratory

A concerted effort has been made to increase the opportunities for undergraduate students to address scientific problems employing the processes used by practicing chemists. As part of this effort, an infrared (IR) spectroscopy and molecular modeling experiment was developed for the first-year general chemistry laboratory course. In the experiment, students explore the dynamic nature of the covalent bond in a hands-on, inquiry-based approach by experimenting with mass and spring systems, using molecular modeling software, and performing IR spectroscopy on a series of structurally related compounds. Students see the effect of bond order, atomic size, and molecular weight on bond strength, bond length, and vibrational frequency. As an added benefit, students are introduced to scientific instrumentation and tools that can then be expanded upon in later laboratory classes..