This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Glyoxal, the smallest alpha-dicarbonyl, is formed in the atmospheric oxidation of many hydrocarbons. It is becoming increasingly interesting to atmospheric scientists due to the fact that it partitions into atmospheric aerosol much more quickly than its vapor pressure would suggest. Recent studies have shown that glyoxal reacts with the ammonia in ammonium sulfate aerosol to irreversibly form substituted imidazole compounds. While this reaction is not new to chemists, this is the first time imidazoles have been identified within the aerosol in the atmospheric chemistry. This study will use uv-visible spectroscopy and NMR to probe the kinetics of the reaction between ammonium sulfate and glyoxal in bulk solution in order to understand the reactions occurring within the aerosol. NMR is vital to this effort so we can unequivocably identify and determine yields of the products in solution, as uv-visible spectroscopy will only give us an idea of rates, but not individual product formation.