02019nam a22002057a 4500 20231120163742.0 231120b ||||| |||| 00| 0 eng d 0021-9584 Sever, Mary Isomerization Kinetics of Hydroxy-Substituted Azobenzenes Using a Modified Commercial Flash Photolysis Spectrometer (Journal Article) Washington DC :American Chemical Society ,2023 2762-2769p. Journal of Chemical Society , Volume 100: Number 7, July 2023 ***______{For Hard Copy, Please visit Library.}________*** Abstract: A laboratory experiment that exposes students to fundamental concepts in kinetics and statistical thermodynamics to study systems of great current interest in nanotechnology by employing a foundational technique in physical chemistry is described. A modified commercial flash photolysis spectrometer was used to study photoinduced isomerization reactions on the millisecond time scale for several hydroxy-substituted azobenzene compounds. The temperature-dependent transient decays were analyzed with an Eyring plot to yield the enthalpy and entropy of activation of the reverse isomerization process. The specific compounds studied were 4-phenylazophenol, 4-methyl-2-(phenylazo)phenol, and 2,4-dihydroxyazobenzene in ethanol solvent. Instrumental modifications include substitution of a UV-LED for the probe light source and use of a thin polyimide film heater adhered to the side of the sample cuvette to control temperature. Collection of experimental data and the subsequent plotting and analysis are easily accomplished by upper-division chemistry students and the results are consistently good, comparing well with literature values. Azobenzene| Isomerization| Kinetic parameters| Mass spectrometers| physical chemistry| kinetics| photochemistry| nanotechnology Young, Mark A. https://doi.org/10.1021/acs.jchemed.3c00200 PER 0 0 0 0 RIEBPL RIEBPL 2023-11-20 0 2023-11-20 00:00:00 2023-11-20 PER 44973 44972