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A computational experiment investigating common organic chemistry mechanisms has been developed and implemented in a junior/senior-level physical chemistry laboratory course at two institutions. Students investigated various reactions that proceed via S N 1, S N 2, E1, and E2 mechanisms using hybrid Density Functional Theory (DFT). Our pre/post-assessments indicate that students at both institutions were able to better visualize and interpret the 3D representation of transition states, stepwise reaction mechanisms, and reaction coordinate diagrams of the aforementioned reactions.

Students in an upper-level physical chemistry course utilized an open-sourced statistical software package to construct models fitted to experimental pressure–volume data. In the first part of the experiment, students familiarize themselves with model fitting. In the second part of the experiment, students determine which truncated version of the virial equation of state is statistically valid to properly model air. This experiment demonstrates proper multivariable linear regression model construction, along with the nonideality of air.

Nontarget analysis using liquid chromatography–high resolution mass spectrometry (LC–HRMS) is a valuable approach in characterizing for contaminants of emerging concern (CECs) in the environment. In this study, wastewater and surface water samples from three locations in Manila, Philippines were analyzed for CECs using a nontarget analysis approach with an LC-Orbitrap. A previously optimized semiautomated workflow was used for data processing with Compound Discoverer. A total of 157 compounds were identified, with 21 confirmed with reference standards, 83 confirmed with evidence from a mass spectral library (mzCloud), and 53 tentatively identified using in silico fragmentation (MetFrag). These compounds include pharmaceuticals such as antibiotics, antifungal, and antihypertensive compounds, human metabolites, natural products, pesticides, and industrial chemicals. Compounds confirmed with reference standards include antibiotics ciprofloxacin, clarithromycin, acetyl-sulfamethoxazole, and trimethoprim (2 to 19 ng/L), and antifungal compounds carbendazim and climbazole (3–47 ng/L). The pesticides diethyltoluamide (DEET) and diuron were also detected (37 ng/L). The utility of a preliminary multivariable linear regression quality structure-retention relationship (QSRR) model based on quantum chemical molecular descriptors is demonstrated. This study demonstrates the importance of using tools and software that are helpful for annotating HRMS data and reporting detections according to a standardized classification system. The detection of several CECs in wastewater and surface water samples show the importance of performing nontarget analysis in determining occurrence of CECs in the environment.