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Perovskite solar cells (PSCs) have garnered increasing attention as a promising photovoltaic technology. PSCs have shown rapid improvement in efficiency compared to other photovoltaic technologies, demonstrating their significantly high potential. Due to their desirable features, such as high-power conversion efficiency, being a solution-based technique, being lightweight, low cost, and flexible, PSCs are considered promising candidates for commercial applications. This article discusses the fundamentals of perovskite photovoltaics and their future scope through undergraduate students' experiments. A group of undergraduate students deposited uniform films of each material using a spin-coating technique and annealing, and then analysed the resulting thin-film properties via X-ray diffraction, ultraviolet-visible spectroscopy, photoluminescence spectroscopy, scanning electron microscopy, and current–voltage measurements. The undergraduate students were able to fabricate simple PSC modules, and critically interpret and compare their results. They successfully fabricated highly efficient solar cell modules and achieved a power conversion efficiency of 9.10%. Further, they demonstrated a working model of smart traffic lights and smart windows by using the fabricated PSC module to understand the potential of PSCs in real-world applications. [ABSTRACT FROM AUTHOR]

Abstract Members of the Interactive Online Network of Inorganic Chemists (IONiC) report the development and sustained efforts to provide virtual professional development sessions: Supporting Learning with Interactive Teaching: a Hosted, Engaging Roundtable (SLiThEr). SLiThEr’s emerged from a community need at the start of the COVID-19 pandemic; since then, SLiThEr’s have become a standard event for the IONiC community. SLiThEr’s are real- time virtual community events, after which a recording of the SLiThEr is posted on the IONiC YouTube channel. In this paper, an overview of the structure, format, and emergence of SLiThEr’s is reported, followed by evaluation of SLiThEr offerings, a plan for future SLiThEr offerings, and a discussion of how SLiThEr’s impact teaching practice. Graphical Abstract

Members of the Interactive Online Network of Inorganic Chemists (IONiC) report the development and sustained efforts to provide virtual professional development sessions: Supporting Learning with Interactive Teaching: a Hosted, Engaging Roundtable (SLiThEr). SLiThEr's emerged from a community need at the start of the COVID-19 pandemic; since then, SLiThEr's have become a standard event for the IONiC community. SLiThEr's are real- time virtual community events, after which a recording of the SLiThEr is posted on the IONiC YouTube channel. In this paper, an overview of the structure, format, and emergence of SLiThEr's is reported, followed by evaluation of SLiThEr offerings, a plan for future SLiThEr offerings, and a discussion of how SLiThEr's impact teaching practice. [ABSTRACT FROM AUTHOR]

Despite being a traditional coursework for pre‐medical and medical students around the globe, biochemistry education suffers from a lack of positive appreciation due to the nature of the subject combined with deficiency of teaching modalities. A first semester biochemistry course was designed to include four different teaching modalities: lectures, recitations, case studies, and student presentations. A multi‐item, anonymous, and voluntary questionnaire was distributed to students who had just completed the course and to those who had taken it the previous year. The questionnaire asked students to evaluate the course and how the different modalities affected their learning. These questionnaires took place in a two‐year period between 2020 and 2021. Eighty‐six (46%) of 186 total students responded. The vast majority of respondents agreed with the use of multimodal teaching techniques with respect to its impact on overall preparedness for future coursework, understanding, and enjoyability. Lectures and recitations were found to be the most useful in information retention and learning, although the same were found to be less enjoyable than other modalities. Although case studies and presentations were found to be enjoyable, most students ranked them low in terms of information retention and were the most voted to be removed from the course. There was general agreement between premedical and medical students' perception on the usefulness of the multimodal teaching techniques with respect to medical biochemistry modules and standardized exams. The agreement between cohorts suggests the premedical students accurately evaluated the usefulness of the course for the following year and validates the usefulness of the premedical student surveys. Use of multiple modalities in biochemistry education can be of substantial benefit in engaging and preparing students for further education. [ABSTRACT FROM AUTHOR]

Peer tutoring is a teaching strategy that offers a creative way of getting students more involved and accountable for their own learning in college-level chemistry courses. The authors have found that the `Symmetry and Space Group Tutorial' [Jasinski & Foxman (2007). Symmetry and Space Group Tutorial, V1.55. http://people.brandeis.edu/~foxman1/teaching/indexpr.html] lends itself well to a peer-tutoring approach in a crystallography course for chemistry students. This in-class activity provides an opportunity for students to learn space-group diagrams, understand basic symmetry concepts, organize what they have learned, and explain it to their peers, which leads to a deeper overall understanding of the subject. We report on our experience in planning peer tutoring, advise on best practices, and demonstrate the positive impact on student learning and engagement.

In an upper‐division interdisciplinary laboratory experiment, students use Raman spectroscopy to highlight how the overall structure and conformational order of lipid bilayers can be influenced by their individual phospholipid composition. Students prepare a supported lipid bilayer, as a model cell membrane, by spreading liposomes made of various phospholipids on a solid support. The characterization of phospholipid bilayers, a major component of cellular membranes, can advance our fundamental understanding of important biological phenomena, with significant implications in various fields including drug delivery and development. We use Raman spectroscopy as an analytical tool to investigate the structural and packing properties of model cell membranes. The spectral frequency, intensity, and line‐width of lipid Raman bands are extremely sensitive to structural alterations. This experimental module effectively exposes students to the fundamentals of Raman spectroscopy and teaches students the importance of interdisciplinary education as they integrate concepts from chemical structure, molecular interactions, and analytical spectroscopic techniques to gain a more holistic understanding of biological membrane properties. [ABSTRACT FROM AUTHOR]

[Display omitted] • China's higher education system is fast-growing and facing major challenges in high-quality course development. • An innovative pass-through game (PTG) style teaching is designed by implementing humanistic theory. • A case study of chemical engineering principles course adopting PTG teaching is presented, showing great improvement in students' performance. The humanistic view has a far-reaching influence on education. This work presents an innovative pass-through game style teaching approach to improve the quality of classroom teaching in the rapid development of higher education in China, and creating a model for classroom teaching with a humanistic view. A case study in teaching "Chemical Engineering Principles 2" for undergraduate students in Quzhou University is presented, and great improvement in students' tests and national competition results, and their satisfaction have been demonstrated. Through the pass-through game style teaching, individual attention for students in big class can be realized. [ABSTRACT FROM AUTHOR]

A laboratory exercise for undergraduate advanced students of enzymology and biocatalysis is presented. Since enzyme assays can be quenched or continuous, this experiment compares the performance of two quenching agents for lactase, in a continuous setup. Enzymatic activity of β‐galactosidase (Aspergillus oryzae) was determined based on the release of 4‐nitrophenol from 4‐nitrophenyl β‐D‐galactopyranoside using a microplate reader. Sodium carbonate and borate buffer were tested as quenching agents, and experimental control was the unstopped assay. Based on released 4‐nitrophenol, enzyme activity, and rate constant k, the students could assess the performance of each termination agent. The experiment promotes disciplinary and transversal competencies, including research‐based learning, critical thinking, and introduce the students to high‐throughput techniques that are common in the research and development environment. [ABSTRACT FROM AUTHOR]

As society becomes more technologically complex, post-secondary institutions have responded by incorporating science-based courses in the non-science curriculum. As chemist, we are often called upon to teach these courses and explain complex concepts to learners with limited science background. An effective method to engage students with the material is using demonstrations. In this study, we examine the use of science-based demonstration in our third-year science course for non-science students. [ABSTRACT FROM AUTHOR]

The goal of this laboratory exercise is to give upper‐level undergraduate students an introduction to sterile technique in mammalian cell culture and metabolism. The experiment can be completed within a 3‐h lab period and can be performed either in conjunction with other biochemistry/metabolism experiments or used as a stand‐alone experiment. In this experiment, students are tasked with relating the acidification of cell culture medium to metabolism in order to elucidate the mechanism of action for a compound. Students can relate their experimental results to topics covered on glycolysis and oxidative phosphorylation in upper‐level biochemistry classes as well as gain valuable experience relating metabolism to drug discovery. [ABSTRACT FROM AUTHOR]

Förster resonance energy transfer (FRET) is the basis for many techniques used in biomedical research. Due to its wide use in molecular sensing, FRET is commonly introduced in many biology, chemistry, and physics courses. While FRET is of great importance in the biophysical sciences, the complexity and difficulty of constructing FRET experiments has resulted in limited usage in undergraduate laboratory settings. Here, we present a practical undergraduate laboratory experiment for teaching FRET using a diverse set of green‐emitting fluorescent proteins (FPs) as donors for a cross‐linked Yukon orange FP. This laboratory experiment enables students to make the connection of basic lab procedures to real world applications and can be applied to molecular biology, biochemistry, physical chemistry, and biophysical laboratory courses. Published 2018. This article is a U.S. Government work and is in the public domain in the USA., 46(5):516–522, 2018. [ABSTRACT FROM AUTHOR]

We described a method for electrophoretic separation of food dyes on a thread-based microfluidic analytical device. A cross channel thread-based microfluidic analytical device was fabricated and used to separate a mixture of food dyes. By controlling and adjusting the potentials applied onto four reservoirs, carmine and sunset yellow could be separated within 2 min. This method has the advantages of low cost, fast separation, and easy fabrication and operation, which make this very suitable for performing as a demonstration in universities. The students enjoyed this demonstration and presented some interesting and constructive questions after the demonstration, which indicated that the students were interested in the demonstration. This demonstration could also be modified to be a laboratory experiment which could be carried out within 3 h. [ABSTRACT FROM AUTHOR]

Scientific Data Analysis Toolkit (SDAT) is a rigorous, versatile, and user-friendly data analysis add-in application for Microsoft Excel for Windows (PC). SDAT uses the familiar Excel environment to carry out most of the analytical tasks used in data analysis. It has been designed for student use in manipulating and analyzing data encountered in the physical and biological sciences, from first-year courses, to the graduate level, and in research. A particularly useful feature of SDAT is its ability to perform rigorous regression analysis using both standard and user-defined model functions. This tool, which can accommodate up to seven fitting parameters, provides the standard deviation of regression of the fit, the standard uncertainties of the fitting parameters, and the covariance matrix. It also supports weighted regression analysis. SDAT includes the following functionalities: Descriptive Statistics, Integrate, Differentiate, Smooth, Spline, Plot, and Regression Analysis. The use of the Regression Analysis tool is illustrated with several examples including the unweighted and weighted analysis of the nonlinear and linearized forms an exponential decay and an example of the use of the covariance term in a propagation of errors calculation. Other example topics are chemical and enzyme kinetics, vapor pressure, and quantum chemistry computational results. SDAT is provided as associated content. [ABSTRACT FROM AUTHOR]

Many chemistry laboratory exercises follow a given protocol with known results. Such traditional laboratories rarely give students an accurate representation of how research is conducted, the scientific practices involved in research, and the ownership that accompanies developing and carrying out an independent project. Several laboratory reforms have sought to overcome these limitations, including the creation of course-based undergraduate research experiences (CUREs). The CURE design is meant to emulate authentic research in the teaching laboratory by having students perform novel experiments with unknown results. In this article, we describe our implementation of a CURE for an upper-level physical chemistry laboratory course. Our students carried out novel research using molecular dynamics simulations, isothermal titration calorimetry, and stopped-flow kinetics to study ligand binding to the protein human serum albumin. We studied the effects of the CURE laboratory redesign via a mixed-methods approach. We use the CURE Survey by Lopatto and colleagues to record students' perceived gains in course elements and benefits. We also conducted student interviews to gain an in-depth view of their experience with the CURE laboratory. Our findings suggest that implementing a CURE in an upper-level chemistry laboratory results in similar outcomes to other CURE experiences (which most often occur at the introductory level), can standardize undergraduate research training, and can increase student ownership of laboratory work. We conclude that developing CURE courses for upper-level chemistry courses is an effective way of enhancing undergraduate laboratory training and increasing student experience with research. [ABSTRACT FROM AUTHOR]

An iridium(III)-mediated C-H functionalization sequence involving a concerted cyclometalation-deprotonation/migratory insertion pathway is reported for the undergraduate chemistry laboratory. The air- and water-stable iridacycle intermediates are readily isolated and characterized by NMR spectroscopy. Both steps of the experiment are performed at room temperature under benchtop conditions, rendering the protocol suitable for a wide range of student skill levels. [ABSTRACT FROM AUTHOR]

For the least-squares analysis of data having multiple uncertain variables, the generally accepted best solution comes from minimizing the sum of weighted squared residuals over all uncertain variables, with, for example, weights in xi taken as inversely proportional to the variance σxi2. A complication in this method, here called "total variance" (TV), is the need to calculate residuals σi in every uncertain variable. In x-y problems, that means adjustments must be obtained for x as well as for the customary y. However, for the straight-line fit model, there is a simpler procedure, a version of effective variance (EV) methods, that requires only the residuals in y and agrees exactly with the TV method. Furthermore, Monte Carlo calculations have shown that this EV2 method is statistically comparable to the TV method for many common nonlinear fit models. This method is easy to code for computation in Excel and programs like KaleidaGraph, as is illustrated here for several examples, including implicit nonlinear models. The algorithms yield estimates of both the parameters and their standard errors and can be used as well for more traditional problems requiring weighting in y only. [ABSTRACT FROM AUTHOR]

This laboratory experiment employs an innovative approach to introduce undergraduates to liquid chromatography-tandem mass spectrometry (LC-MS/MS) by developing a method based on multiple reaction monitoring (MRM). During this qualitative investigation, students operated a triple quadrupole mass spectrometer in the MS scan and product ion scan modes to determine precursor and product ions, respectively, for a vanillin, ethyl vanillin, and coumarin standard mixture. After identifying precursor → product ion transitions, students conducted a 2 min liquid chromatography run in MRM mode. Students were astonished by the speed, selectivity, and sensitivity of the LC-MS/MS method compared to that of a liquid chromatograph with ultraviolet detection. [ABSTRACT FROM AUTHOR]

31P{¹H} nuclear magnetic resonance spectroscopy is a particularly useful tool for studying the reactions of P-donor ligands such as phosphines and phosphites with transition metals and other Lewis bases because the reactions take place on the nonbonding pair of electrons on the phosphorus. In addition, 31P has a 100% natural abundance and a high gyromagnetic ratio resulting in a high sensitivity that allows the spectra to be recorded using small amounts of sample. An activity that combines air-sensitive synthesis of transition metal complexes of P-donor ligands and the characterization of these complexes with 31P{¹H} NMR spectroscopy has been developed for an upper-division, laboratory-based inorganic course. This laboratory familiarizes students with this useful nucleus for NMR spectroscopy and allows them to study the factors that affect the 31P{¹H} NMR chemical shifts of phosphorus-donor ligands and their transition metal complexes. Details of the activity, including procedure and pretest, are provided. Alternative methods and presentations are also proposed. [ABSTRACT FROM AUTHOR]

The role of practical work in the training of student teachers is central to the development of their future pedagogy and practice. However, not all laboratory based activities give sufficient challenge in the development of both cognitive and practical skills. The activity proposed in this paper helps reinforce an understanding of reaction kinetics through a study of the reaction of zinc with sulfuric acid. In this study, the observed reaction kinetics conflicted with the typical expectation, which offered a problem to motivate an inquirybased activity. [ABSTRACT FROM AUTHOR]

The scale-invariant way to analyze two-dimensional experimental and theoretical data with statistical errors in both the independent and dependent variables is revisited by using what we call the triangular linear regression method. This is compared to the standard least-squares fit approach by applying it to typical simple sets of example data from the actual chemical literature. A new add-in for Microsoft Excel, LinEstXY, and ready-to-use formulas for the scale-invariant method are provided. [ABSTRACT FROM AUTHOR]

A Sonogashira experiment was transformed into a problem-based learning platform for third-year undergraduate students. Given a target that could be synthesized in a single step, students worked in groups to investigate which method was the best for large-scale production. Through this practical scenario, students learn to conduct a literature search, select procedures, practice their synthesis skills, and evaluate their results in a real-world context. [ABSTRACT FROM AUTHOR]

A classical nonlinear system, the "Brusselator", was used to illustrate the modeling and simulation of oscillating chemical systems using stability analysis techniques with modern software tools such as Comsol Multiphysics, Matlab, and Excel. A systematic approach is proposed in order to establish a regime of parametric conditions that lead to oscillations in chemical systems. A Matlab script that symbolically finds the equilibrium points of the system, and the Jacobian of the assembly matrix at equilibrium was written. The Matlab script also calculates the trace, determinant and discriminant of the Jacobian and finds the critical points for which the trace and determinant are zero. An emphasis on finding the bifurcation points is made in the simulations and on the conditions for the onset of limit cycles, which are of most interest in biological systems. [ABSTRACT FROM AUTHOR]

A laboratory experiment in which students recycle silver and platinum selectively from spent screen-printed platinum electrodes is described. The recovered silver in solution is used to show its spontaneous redox reaction with a copper sheet. The recovered platinum is electrodeposited onto a screen-printed carbon electrode to develop a sensor for hydrogen peroxide quantification in a commercially available hair lightener. The experiment is designed for a 3 h laboratory period and can be adapted for upper-division undergraduate education, graduate education, or even research students in electrochemistry, environmental chemistry, analytical chemistry, materials science, chemical engineering, or physical chemistry laboratories. It allows students to train in adequately handling strong acids, working in fume hoods, and neutralizing acid gases. It also allows one to teach the basics of metal recycling and enables students to learn the fundamentals of electrochemical sensing. The experiment also helps to raise student awareness of waste disposal problems and how recycling can help to reduce the amount of waste that we create. [ABSTRACT FROM AUTHOR]

An undergraduate organic chemistry laboratory experiment that provides an introduction to the concepts and practices of photoredox catalysis is reported. While undergraduate-level photochemistry experiments typically place emphasis on analytical properties of catalysts rather than synthetic applications, this experiment showcases the power and versatility of photoredox chemistry in modern organic syntheses. A hypothesis-driven approach is utilized as students apply chemical reasoning to formulate hypotheses predicting the relative catalytic activity of Ru(bpy)32+ and Ru(bpm)32+, which differ slightly in ligand structure. Students work collaboratively to obtain conversion data in [2 + 2] cycloadditions catalyzed by Ru(bpy)32+ and Ru(bpm)32+, and use the data to support or refute their hypotheses. The operationally straightforward experimental protocol has been shown to be robust and reproducible, providing unambiguous results that facilitate student interpretation. Furthermore, the experiment trains students in chemical thinking needed for conducting research. [ABSTRACT FROM AUTHOR]

Here we present a new undergraduate laboratory that will introduce the concepts of time-resolved spectroscopy and provide insight into the natural time scales on which chemical dynamics occur through direct measurement. A quantitative treatment of the acquired data will provide a deeper understanding of the role of quantum mechanics and various phenomenological expressions in predicting kinetic rates for fluorescence, phosphorescence, and nonradiative decay mechanisms. This laboratory framework focuses specifically on spectroscopy in the nanosecond regime -- assisted by various steady-state spectroscopic techniques -- in order to fully characterize the electronic structure and the picosecond-to-microsecond dynamics of the dye eosin B. There is great flexibility in both the recommended lab duration (1 week to several months) and course level (upper-division to graduate) due to the numerous additional experiments that may be performed at varying levels of difficulty. The necessary components include pump and probe light sources, photodiode detectors, a programmable signal delay generator, and an oscilloscope for measurements with requisite resolution. The cost of building this experiment from scratch is less than $20,000 at the time of publication, but costs are expected to decrease over time and alternate excitation sources are available. Although this lab requires some expertise with optical spectroscopy to initially build and troubleshoot, use by students has been a straightforward and valuable experience. [ABSTRACT FROM AUTHOR]

Explain Everything is an interactive, user-friendly, and easily accessible app for mobile devices. The interactive app-based teaching methods discussed here can be adopted in any STEM or non-STEM course. This app allows instructors to take advantage of both the chalkboard and PowerPoint slides on a single platform, create videos for lecture captures and flipped/online classrooms, and virtually assist upper-level students with the development of soft skills through personalized videos/PDFs. Feedback data from students highlight multiple benefits from the use of this app. This app aids better visualization of concepts, promotes ubiquitous learning opportunities for students, and provides personalized feedback on documents in seminar courses. [ABSTRACT FROM AUTHOR]

A computational chemistry exercise for the undergraduate physical chemistry laboratory is described. In this exercise, students use the molecular dynamics package Amber to generate trajectories of bulk liquid water for 4 different water models (TIP3P, OPC, SPC/E, and TIP4Pew). Students then process the trajectory to calculate structural (radial distribution functions) and dynamic (diffusion coefficients) properties of water that they compare to experimental values and to the other models. On the basis of these comparisons, students are also able to draw conclusions regarding the relative efficacy of these water models at modeling properties of real water. [ABSTRACT FROM AUTHOR]

The reported project-based laboratory unit introduces upper-division undergraduate students to the basics of computer-aided drug discovery as a part of a computational chemistry laboratory course. The students learn to perform model binding of organic molecules (ligands) to the DNA minor groove with computer-aided drug discovery (CADD) tools. The purpose of this laboratory unit is to dock diminazene and its derivatives to DNA, to estimate their binding energies, and to elucidate details of DNA- ligand intermolecular interactions. The computational procedure also helps to screen binding capabilities of DNA ligands. [ABSTRACT FROM AUTHOR]

An integrated laboratory experiment applying concepts and techniques from organic chemistry, inorganic chemistry, and instrumental analysis is presented for use in the undergraduate curriculum. This experiment highlights the synthesis, characterization, and use of tris(2-pyridylmethyl)amine (TPMA) to make complexes with different metal salts. It incorporates laboratory practices such as literature searches, multistep synthesis, reaction mechanisms, NMR spectroscopy, and X-ray crystallography. [ABSTRACT FROM AUTHOR]

Fluorescence spectroscopy experiments are a frequently taught as part of upper-division teaching laboratories. To expose undergraduate students to an applied fluorescence technique, a corrosion detection method, using quenching, was adapted from authentic research for an instrumental analysis laboratory. In the experiment, students acquire fluorescence spectra of sensing molecules in the presence of mock sculpture samples and discuss the condition of the sculptures based on the levels of soluble iron detected. This real-world-based experiment allows students the chance to engage with ongoing research and further understand the challenges with early detection of corrosion. Most students successfully completed the experiment, wrote a journal-quality report, and met the learning outcomes. [ABSTRACT FROM AUTHOR]

Many types of batteries power an ever-growing number of devices. Electrochemical devices like batteries and fuel cells can, in principle, exceed Carnot efficiency for energy conversion. In this novel laboratory experiment, students explore the partitioning of the enthalpy change of a battery's electrochemical reaction between useful electrical work and waste heat, AH = welec + q. Work is measured by monitoring cell potential and current during battery discharge; waste heat evolved at the battery is simultaneously measured in a calorimeter. Results from discharging AA-size "alkaline" batteries are presented. Data for nickel-cadmium, nickel-metal hydride; a D-size, single cell, lead-acid storage battery; and Zn/Ag2O watch batteries are also presented in the Supporting Information. [ABSTRACT FROM AUTHOR]

3D printing technology has an enormous potential to apply to chemical engineering education. In this paper, we describe several designs of 3D printed mesoreactors (Y-shape, T-shape, and Long channel shape) using the following steps: reactor sketching, CAD modeling, and reactor printing. With a focus on continuous plug flow mesoreactors (PFRs, i.d. = 2 mm), fluid mixing phenomena were explored by using a passive mixing method. The small channel of mesoreactors facilitates the stability of a laminar flow in the system at low Reynolds number. With changes in flow rates (0.2 and 4.0 mL/min) and channel geometry (0° and 90° outlet angle), fluid mixing was controlled. Our results provided that 3D printed mesoreactors can be possibly used in teaching fluid dynamics, chemical kinetics, and reaction engineering, which are main courses of the chemical engineering undergraduate program. Furthermore, the cost of mesoreactor printing was suitable (<$1.00/microreactor) for education. [ABSTRACT FROM AUTHOR]

ACS Examinations provide a lens through which to examine historical changes in topic coverage via analyses of course-specific examinations. This study is an extension of work completed previously by the ACS Exams Research Staff and collaborators in general chemistry, organic chemistry, and physical chemistry to explore content changes in the principal courses of the postsecondary chemistry curriculum. In this study, we consider how inorganic chemistry content coverage has varied over a 55-year period since the first inorganic chemistry ACS Examination was released in 1961. A total of 860 items was evaluated on the basis of problem type (i.e., algorithmic, conceptual, or recall), use of visual-spatial or reference components, and content coverage. Our analyses identify core content areas in the inorganic chemistry curriculum, consistent with those reported in faculty surveys. Each examination also contained questions addressing a variety of specialty areas that vary widely within the discipline between 1961 and 2016. Unlike the results from historical reviews of general chemistry and organic chemistry ACS Examinations, we observe great variability across the 13 inorganic chemistry examinations with an absence of strong trends in inclusion or exclusion of problem types, visual-spatial or reference components, or content across the 13 exams analyzed. Our results offer a framework for using historical ACS Examinations as a tool to make decisions about the future of content coverage in postsecondary inorganic chemistry education. [ABSTRACT FROM AUTHOR]

Multifunctional chemical analysis (MCA) systems provide a viable alternative for large scale instruction while supporting a hands-on approach to more advanced instrumentation. These systems are robust and typically use student stations connected to a remote central computer for data collection, minimizing the need for computers at every student workspace. MCA networks offer multiple measurement capabilities; however, constant-current coulometry is still an uncommon MCA option. The characterization of an assembled teaching coulometry instrument for online data acquisition using an MCA system is described. A constant-current source connected to nonisolated Pt electrodes in a 150 mL beaker serving as the reaction cell caused the iodine titrant to be electrochemically generated for subsequent reaction with the analyte reducing agent. A photoresistor mounted on the stir plate below the beaker monitored the darkening of the solution due to formation of the starch-iodine complex. The change in voltage from an operational amplifier circuit permitted this titration curve to be stored by the MCA system for subsequent graphical analysis by Excel. Characterization of the instrument for direct analyte determination is performed with ascorbic acid, thiols, thiosulfate, and bisulfite. The number of electrons per mole of thiol for iodine titration of glutathione and N-acetylcysteine varied differently as a function of pH, indicating different reaction pathways. Ascorbic acid and the thiols are determined in dietary supplements with a recovery of 90-100%, and % RSDs of triplicate measurements ranged from 0.7% to 5%. [ABSTRACT FROM AUTHOR]

Randy Olson's book, Don't Be Such a Scientist: Talking Substance in an Age of Style, was used to supplement a senior seminar in nanomaterials. While students learned about the chemistry behind useful properties of nanomaterials, they also analyzed how nanomaterials applications are presented to the public through advertising, science news, and popular culture artifacts. By using Don't Be Such a Scientist, students learned how scientists can fail at communicating with the public and how they can become more effective communicators. To experience communicating to nonexperts, they presented outreach projects such as a video, activity, or discussion on nanomaterials. Example student projects in nanomaterials are discussed; however, Don't Be Such a Scientist could easily be incorporated into a variety of scientific courses to include effective scientific communication to the public, a meaningful skill for all scientists and science students. [ABSTRACT FROM AUTHOR]

The application of the Reaction Monte Carlo (RxMC) algorithm to standard textbook problems in chemical reaction equilibria is discussed. The RxMC method is a molecular simulation algorithm for studying the equilibrium properties of reactive systems, and therefore provides the opportunity to develop computer-based "experiments" for the analysis of a wide range of chemical reactions. As the conditions of the reaction can be precisely controlled in these simulations, students can rather easily perform "virtual experiments", and then compare the resulting compositions, extents of reaction, etc. with the predictions obtained using the relations of macroscopic thermodynamics. Students can also use these "experiments" to directly test the guidelines suggested by Le Châtelier's principle, and even study situations in which exceptions to these guidelines are known to occur. These computer-based analyses can therefore be used as the basis of various useful and instructive homework assignments, or group projects, which can also touch upon important topics in molecular thermodynamics. Simulations can be performed on ideal gases (i.e., noninteracting particles), and depending upon the level of the student audience, the simulation algorithms can be modified to describe reactions in nonideal systems, in which the intermolecular potential energies between the molecules need to be considered. Thus, concepts from molecular thermodynamics can also be incorporated into the analyses of chemical reaction equilibria. [ABSTRACT FROM AUTHOR]

Zero-order systems provide an interesting opportunity for students to think about the underlying mechanism behind the physical phenomena being modeled. The work reported here is part of a larger study that seeks to characterize how students integrate chemistry and mathematics in the context of chemical kinetics. Thirty-six general chemistry students, five physical chemistry students, and three chemical engineering students were asked to think aloud as they responded to an interview prompt about the half-life of a catalyst-driven zero-order reaction. Our findings revealed that students often described zero-order in mathematical terms (i.e., the zero-order rate law, integrated rate law, and graphical representation), but lacked a clear understanding of the particulate nature of zero-order systems. Results also indicated students have productive discipline-specific conceptions of catalysts but less productive ideas regarding half-life, expressing a limited view that seemed restricted to first-order decay reactions. Analysis of student problem solving further revealed patterns among this type of half-life reasoning. Our work suggests the need for instruction that varies context to promote a more holistic understanding of chemical kinetics concepts. [ABSTRACT FROM AUTHOR]

The concept of energy is of central significance, as it is a core disciplinary idea in chemistry and a cross-cutting concept in the sciences. This study sought to investigate student understanding of energetics and associated thermodynamic functions in chemical reactions and processes across a sample of introductory-level undergraduate chemistry students, upper-level undergraduate chemistry students, and physical chemistry graduate students. Participants were interviewed using an interview-about-events protocol, interacting with reagents that underwent chemical reactions or dissolutions. Analysis of the interview data revealed specific student difficulties with content, as well as common reasoning patterns used by students when considering energy changes in observed reactions and processes. Implications for curriculum and instruction are discussed. [ABSTRACT FROM AUTHOR]

Sycamore wood is a source of a blue, fluorescent, aqueous extract that exhibits dramatic pH dependence. The sycamore tree has two most prevalent species in the eastern USA, the native American sycamore (Platanus occidentalis) and the more globally present hybrid London planetree (Platanus x acerifolia), both being equally amenable to the demonstration. The primary fluorescent substance in the aqueous extract of the wood is scopoletin (6- methoxy-7-hydroxycoumarin), a secondary metabolite of the tree generated in response to the injury of harvesting a specimen from the live tree. The fluorescence responds well to black light (365 nm) and violet (405 nm) excitation. The easy, attractive, and inexpensive demonstration of the extraction and fluorescence is described, and it is adaptable to hands-on activities like that described for narra wood (Pterocarpus indicus) earlier in this Journal. Updated information is provided on Pterocarpus wood species that exhibit excellent fluorescence in a similar manner. [ABSTRACT FROM AUTHOR]

Green chemistry and sustainability have garnered more awareness in the chemical industry in recent years, but green chemistry classes are still not commonplace for either the undergraduate or graduate student curriculum. Additionally, many departments are seeking avenues to reach greater numbers and types of learners through online courses. To address both needs, a small group of chemistry graduate students set out to design a 3-credit-hour upper-level online green chemistry course targeted at students most likely to apply green chemistry concepts in their future careers. The goals for the course included education in the basics of green chemistry (history, metrics, methodologies) along with opportunities to apply what they have learned and communicate it to a general audience. This process of developing modules and assessments for the discovery and application of green chemistry principles has enabled a supplementary education for the graduate students as well. Herein, the specific motivations of the graduate students to design the course, how green chemistry was presented to students in an online format, and how students responded to this type of class are provided. [ABSTRACT FROM AUTHOR]

Three concepts necessary for understanding the greenhouse effect are infrared radiation, absorption of infrared radiation by greenhouse gases, and steady-state energy flow. Herein, we describe adaptations to three classic demonstrations for teaching these concepts. William Hershel's discovery of infrared radiation has been adapted into a fast and reliable demonstration using a pyranometer. We provide guidelines for building a ball-and-spring model of carbon dioxide that demonstrates the absorption of IR and the three fundamental vibrational modes of carbon dioxide and their relative frequencies. Finally, we describe an adaptation of Blanck's plastic water-flow device to demonstrate how adding greenhouse gases can alter the steady-state flow of energy through the atmosphere. [ABSTRACT FROM AUTHOR]

Le Châtelier's principle is used as a basis to derive an expression to calculate solution pH during titrations that involve only strong acids and strong bases. Central to this model are the reaction quotient and a reequilibration term that represents the extent of neutralization during a titration. Unlike the method traditionally taught to students to determine the pH of these acid-base mixtures, the expression obtained is exact and applies throughout the entire range of a titration curve without the need for modification or segmentation. The expression is the same as one that is obtainable using charge balance; however, the present derivation applies Le Châtelier's principle instead, and therefore remains within the scope of a general chemistry curriculum. Instructors are then able to reinforce and deepen understanding of previously learned concepts in acid-base chemistry while connecting them to chemical equilibrium and titration curves. [ABSTRACT FROM AUTHOR]

Service-learning (SL) is an active learning approach that connects the knowledge a student acquires in the classroom to an application that benefits the community. Increasingly popular in the chemistry curriculum, service-learning is reported to provide student benefits including improved cognitive goals; increased academic, interpersonal, and leadership skills; increased ability to apply course concepts to real-world situations; and increased community engagement. For the work reported here, an analytical chemistry laboratory was modified to include a service-learning component with the goal of allowing students to apply their newly acquired analytical skills to relevant, real-world samples; to learn new analytical techniques; and to develop professional communication skills. Students implemented a study of the wastewater effluent at the Orlando Easterly Wetlands, an engineered water polishing facility that removes nutrients from treated wastewater. Students designed a sampling strategy, collected samples in the field, and performed standard analysis on the water, including pH, chloride, total dissolved solids, and phosphorus. Students also tested the water for the artificial sweetener, sucralose, and characterized the concentration throughout the flow path of the wetlands. Sucralose has been proposed as an indicator of contamination of natural waters by anthropogenic waste. This type of analysis has not been performed for this public utility until now, and the students shared the results in a public seminar. Student learning outcomes were compared to those in a conventional section, with SL students showing comparable subject mastery and improved self-efficacy. [ABSTRACT FROM AUTHOR]

Perovskite solar cells have garnered exponential research interest due to their facile fabrication, solution processability, and low cost. However, there have been limited efforts to integrate this class of materials into the undergraduate laboratory curriculum. Therefore, we designed an integrated laboratory experiment in our upper-division integrated laboratory sequence to teach students about research procedures and tools used in physical, organic, inorganic, and materials chemistry. This laboratory sequence involves conversion of sunlight to electricity, which is one of the most challenging renewable energy issues we are facing as a society. In this work, upper-level undergraduates study four variables affecting the morphology and optical properties of perovskites: solvent treatment, percent of water added to a precursor mixture, cation substitution, and precursor temperature. To do so, students deposit uniform films of the material using spin-coating and annealing, and then probe the resulting film properties via scanning electron microscopy, X-ray diffraction, solid-state UV-vis spectroscopy, and current-voltage measurements. Students are able to execute the simple experimental setups and critically interpret, and compare, their results. Further, students are asked to question and understand structure-property relationships to arrive at a fuller understanding of the light-to-electricity conversion process. Importantly, this laboratory prepares students for cutting-edge inorganic and materials research topics. [ABSTRACT FROM AUTHOR]

Manga are graphic novels that are considered to have the potential to effectively convey concepts and engage readers. The efficacy of manga has been validated for chemical safety education to students in three universities in Japan, Taiwan, and Thailand. Students were asked to examine a photo to identify hazards and hazardous behaviors that can potentially lead to accidents before and after reading a manga that explains the risk of fires and explosions. The identified hazards/hazardous behaviors were classified into seven categories, and the average number of hazards/hazardous behaviors was determined in each category. The differences before and after the lesson were analyzed to evaluate the effectiveness of manga as an educational tool. In the students' answers, in all three of the universities, some common features were observed: Subjects easily identified certain hazardous conditions in the photo, particularly noting deficient or unsuitable personal protective equipment. The hazards/hazardous behaviors that can potentially result in ignitions, fires, and explosions were more likely to be identified after the lesson. Many students found the manga a helpful tool for learning chemical safety. [ABSTRACT FROM AUTHOR]

Identification and quantification of an unknown illicit drug (cocaine) from both simulated drug paraphernalia and simulated urine can be achieved via direct analysis in real time (DART) triple quadrupole linear ion trap (QTRAP) mass spectrometry (MS). We describe a novel, hands-on laboratory activity which utilizes the recent DART technology interfaced with a tandem mass spectrometer for the purpose of integrating recent technology into a quantitative analysis course, reinforcing chemical concepts, improving critical thinking and written communication skills, and providing a context for real-life analyses. The hands-on laboratory activity requires students to use good laboratory practice, perform common laboratory calculations, and think critically to perform both qualitative and quantitative analyses and answer real-life forensic questions. Assessments include prelaboratory activity questions, observations during the activity, postlaboratory activity written report, and anonymous summative activity. [ABSTRACT FROM AUTHOR]

Although experimental design is important in many fields and industries, most undergraduate students do not get exposure to this in a standard lab curriculum. This work describes a student-designed, multiple-week, flexible chemistry experiment with environmental applications that include factorial experimental design and analysis of variance statistical analysis. Through the experiment, students attempt to gain a better understanding of activated carbon adsorption of dyes under a set of factors, which could include type of dye, type of carbon, pH, salinity, hardness, and time of contact, each at multiple levels. The experiment is easily adaptable for a range of student enrollments and uses only common laboratory glassware and any visible spectrometer. [ABSTRACT FROM AUTHOR]