Laboratory studies of the heterogeneous reactions between HNO3 in thin water films on silica surfaces and gaseous NO, CO, CH4, and SO2, proposed as potential "renoxification" mechanisms in the atmosphere, are reported. Transmission FTIR was used to monitor reactants and products on the silica surface and in the gas phase as a function of time. No reaction of CO, CH4, or SO2 was observed; upper limits to the reaction probabilities (gamma(rxn)) are < or = 10(-10) for CO and SO2 and < or = 10(-12) for CH4. However, the reaction of HNO3 with NO does occur with a lower limit for the reaction probability of gammaNO > or = (6 +/- 2) x 10(-9) (2s). The experimental evidence shows that the chemistry is insensitive to whether the substrate is pure silica or borosilicate glass. Nitric acid in its molecular form, and not the nitrate anion form, was shown to be the reactive species, and NH4NO3 was shown not to react with NO. The HNO3-NO reaction could be a significant means of renoxification of nitric acid on the surfaces of buildings and soils in the boundary layer of polluted urban atmospheres. This chemistry may help to resolve some discrepancies between model-predicted ozone and field observations in polluted urban atmospheres.

The American Chemical Society (ACS) Committee on Minority Affairs (CMA) endeavors to support all chemistry faculty and staff as they educate all of our students during this pandemic.While the chemistry education community and the ACS have both provided resources as most institutions transitioned to virtual platforms, this pandemic disproportionally affects our students of color, lower socio-economic and rural backgrounds, and students with disabilities.Specifically, these students must overcome hurdles of technology access, environmental disruptions, and cultural pressures in order to be successful. Therefore, CMA has formulated partnerships with both academic and industrial institutions to highlight some best practices to improve future virtual learning experiences of these oftentimes marginalized students.Specifically, the work presented here examines programs and policies at three academic institutions with very different student body demographics and surrounding learning environments (

An experiment suitable for college junior or senior students in the analytical instrumental analysis laboratory that demonstrates the analysis of PAHs (benzo[a]anthracene, benzo[k]fluoranthene, benzo[a]pyrene, chrysene, and phenanthrene) using absorption and fluorescence spectroscopy is described. This experiment is carried out during one seven-hour instrumental analysis laboratory. It could also be used in a physical chemistry laboratory to demonstrate fundamental spectroscopic and photochemical principles. A Beer–Lambert plot for an absorption peak of each PAH was obtained and used to determine the molar absorptivities. The effect of heavy atoms as quenchers of fluorescence was studied by using 1-bromoheptane and 1,7-dibromoheptane, and Stern–Volmer plots were prepared to determine the ratios of the quenching rate constants to the fluorescence rate constant, k Q/k f. The experiment is also useful as an experiment preceding the determination of PAHs by HPLC with absorption and fluorescence detection as described earlier ( J. Chem. Educ. 1998, 75, 1599).

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Many academic institutions have looked at various ways to make their faculty a more diverse and inclusive group of people that better reflect the demographic swath of their current and future student bodies. This is even more so important in chemistry departments, where there has long been a discussion on the "leaky pipeline" for women and underrepresented groups. The work presented here examines programs and policies at various departments aimed at increasing the diversity of their faculty applicant pool, and compares them against the reception of the general scientific community by way of applicant demographics and the use of a survey instrument designed to ascertain the advertisement language that lends to a more diverse applicant pool. The combination of these results is then used to generate a list of best practices that administrations and academic search committees can use to improve their ability to attract diverse talent.