This laboratory experiment challenges students to identify the country of origin of raw coffee beans from around the world by calculating the percent caffeine and percent water in the supplied samples. The implementation of this experiment enables students in introductory chemistry classes to gain greater understanding of the chemical analysis process and the Beer−Lambert law. Using commercially available raw (green) coffee samples, students extract caffeine from the grounds as an aqueous solution and determine the percent caffeine using UV− vis spectrophotometry. In a second portion of the experiment, raw beans are roasted to determine the percent water content. Using both pieces of data, students are asked to identify the country of origin of given coffee samples in which the percent caffeine ranged from 1.14 to 1.80% (w/w) and the percent water loss ranged from 3.27 to 10.8% (w/w).

publishing original research content that, nonetheless, preserves the journal's identity as a niche for "critical discussion" of contemporary literature in inorganic chemistry.

An advanced research discovery laboratory course in inorganic chemistry has been developed to engage undergraduate students in authentic research experiences directly related to concepts and theory taught in the lecture portion of the course. The 12-week laboratory involves an initial 4 weeks of training experiments on inorganic/organometallic synthesis in air and under inert atmosphere, followed by an 8-week series of research discovery experiments designed to mirror research in a graduate- and/or industry-level inorganic chemistry laboratory. Students are first presented with a research problem related to a coinage metal (group 11: copper, silver, or gold). They are then asked to (1) design a synthetic route using peer-reviewed research articles from the literature with some modification as needed; (2) conduct their proposed synthetic reactions; and (3) characterize products to assess purity and determine the molecular structure, as well as screen their properties toward potential applications.

A covalently linked molecular dyad comprised of terthiophene and C 60 , and a molecular triad comprised of phenothiazine, terthiophene and C 60 have been newly synthesized to probe photoexcited events in solution and at the electropolymerized film. The X-ray structure of the dyad revealed spatial disposition of the donor-acceptor entities without significant intermolecular type interactions. Optical absorbance, fluorescence, and the electrochemical studies were consistent with the structural integrity of the dyad and triad. Further, the TT-C 60 dyad (TT = terthiophene) was found to electropolymerize during multi-cycling of voltammograms. The frontier HOMO and LUMO orbitals of the phenothiazine-terthiophene-C 60 triad (PTZ-TT-C 60 , PTZ = phenothiazine) were found to be located respectively on the phenothiazine-terthiophene and C 60 entities. Free-energy calculations revealed that the excited state charge transfer resulting into the formation of TT •+ -C 60•− in the case of the dyad, and (PTZ-TT) •+ -C 60•− charge separated state in the case of triad to be thermodynamically feasible. Evidence for the occurrence of excited state singlet-singlet energy transfer from 1 TT * to form 1 C 60 * followed by charge transfer was secured from studies involving femtosecond transient absorption studies in polar benzonitrile. Charge stabilization to some extent in the triad compared to that in the dyad was obtained. Attempts were also made to secure evidence of charge separation in the terthiophene-fullerene drop-casted and electropolymerized films on FTO surface.

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