Integrating statistical mechanics with experimental data from the rotational-vibrational spectrum of HCl into the physical chemistry laboratory

CHED 96

Bret R. Findley, Department of Chemistry and Physics, Saint Michael's College, 1 Winooski Park, Colchester, VT 05439 and Steven E. Mylon, mylons@lafayette.edu, Department of Chemistry, Lafayette College, Hugel Science Center, Easton, PA 18042.
We introduce a computer exercise that bridges spectroscopy and thermodynamics using statistical mechanics and the experimental data taken from the commonly used laboratory involving the rotational-vibrational spectrum of HCl. Based on the results from the analysis of their HCl spectrum, students calculate bulk thermodynamic properties such as internal energy, absolute entropy, molar enthalpy of formation, and Gibbs free energy of formation at 298.15 K. This exercise serves as an opportunity for students to review the vibrational-rotational spectrum of HCl, and to apply their knowledge of statistical mechanics. The results show excellent agreement with values found in most introductory physical chemistry texts. This is a nice teaching tool because it uses experimental data to demonstrate the inter-relationship between quantum mechanical states and the bulk thermodynamic properties of a gas.
 

General Posters
7:30 PM-9:30 PM, Sunday, August 19, 2007 BCEC -- Exhibit Hall - B2, Poster

Division of Chemical Education

The 234th ACS National Meeting, Boston, MA, August 19-23, 2007