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The COVID-19 pandemic forced instructors of chemistry lab classes to develop a variety of alternative materials for remote delivery of traditional hands-on content. One solution to this challenge was virtual choose-your-own-adventure (CYOA) laboratories that allowed students to practice realistic decision-making and collect authentic data. With the return to in-person instruction, these CYOA laboratories can be modified into prelab exercises to support and supplement in-person experiments. Four virtual CYOA laboratories were adapted into prelab exercises for an upper-division instrumental analysis course to prepare students for experiments in chromatography method development and electronic circuit design. Students were surveyed to gauge their opinions on the prelabs and their comfort in the laboratory overall. Survey results indicated that students enjoyed the CYOA prelab activities and found them helpful in feeling prepared for experiments and understanding the source and quality of their experimental data. Students who completed the virtual prelabs met more learning objectives in several important categories on lab reports for two electronic circuit design experiments. Virtual CYOA prelabs may be a good way for instructors to expand the depth of their lab curriculum, improve student learning in the lab, and reduce the anxiety that their students feel before complex experiments.

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]

The rise of virtual and online education in recent years has led to the development and popularization of many online tools, notably three-dimensional (3D) models and augmented reality (AR), for visualizing various structures in chemical sciences. The majority of the developed tools focus on either small molecules or biological systems, as information regarding their structure can be easily accessed from online databases or obtained through relatively quick calculations. As such, due to a lack of crystallographic and theoretical data available for nonbiological macromolecules, there is a noticeable lack of accessible online tools for the visualization of polymers in 3D. Herein, using a few sample polymers, we showcase a workflow for the generation of 3D models using molecular dynamics and Blender. The 3D structures can then be hosted on p3d.in, where AR models can be generated automatically. Furthermore, the hosted 3D models can then be shared via quick response (QR) codes and used in various settings without the need to download any applications.

In view of the mounting requirements for courses in nuclear chemistry and radiochemistry, hands-on experience in the separations of radioisotopes is imperative. Three separation techniques commonly used were introduced, coprecipitation, liquid-liquid extraction, and ion-exchange chromatography. Their principles and the associated fundamental thermodynamic concepts are detailed. Their respective experimental applications to the separations of radioisotopes of one rare earth element (europium) and two transition metals (cobalt and nickel) are discussed. In-classroom experimental settings are proposed, and experiment outcomes are presented, which can be beneficial for future implementation within nuclear chemistry and radiochemistry programs in higher education.

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

Ultrafast laser pump-probe spectroscopy is an important and growing field of physical chemistry that allows the measurement of chemical dynamics on their natural time scales, but undergraduate laboratory courses lack examples of such spectroscopy and the interpretation of the dynamics that occur. Here we develop and implement an ultrafast pump-probe spectroscopy experiment for the undergraduate physical chemistry laboratory course at the University of California Berkeley. The goal of the experiment is to expose students to concepts in solid-state chemistry and ultrafast spectroscopy via classic coherent phonon dynamics principles developed by researchers over multiple decades. The experiment utilizes a modern high-repetition-rate 800 nm femtosecond Ti:sapphire laser, split pulses with a variable time delay, and sensitive detection of transient reflectivity signals using the lock-in technique. The experiment involves minimal intervention from students and is therefore easy and safe to implement in the laboratory. Students first perform an intensity autocorrelation measurement on the femtosecond laser pulses to obtain their temporal duration. Then, students measure the pump-probe reflectivity of a single-crystal antimony sample to determine the period of coherent phonon oscillations initiated by an ultrafast pulse excitation, which is analyzed by fitting to a sine wave. Students who completed the experiment in-person obtained good experimental results, and students who took the course remotely due to the COVID-19 pandemic were provided with the data they would have obtained during the experiment to analyze. Evaluation of student written and oral reports reveals that the learning goals were met, and that students gained an appreciation for the field of ultrafast laser-induced chemistry.

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]

In the sciences, the laboratory is one of the most impactful spaces for student learning, engagement, and experience. Prior knowledge gleaned during lecture and laboratory discussion (i.e., a course section designed to further emphasize conceptual content underlying experiments and inform students about laboratory procedures or safety precautions) acts to supplement laboratory performance. With the recent increase in offering traditionally face-to-face courses in remote formats, many educators in the field of organic chemistry have opted to offer online laboratory discussion (LD) sections alongside more traditional face-to-face laboratory discussions. However, research on enrollment in laboratory discussions by modality, as well as their impact on subsequent course performance, is lacking. Conducting a logistic regression analysis, we found that females, students who identified as Black or African American, those with greater average ACT-SAT equivalency scores, and those students who completed organic chemistry LD online in the prior term all had greater odds of enrolling in an online organic chemistry LD course in subsequent academic terms. Additional hierarchical regression analyses indicated that many student- and academic-level factors were predictive of laboratory performance. Notably, when controlling student-level and academic-level characteristics, laboratory performance was higher for students who completed LD online compared to students who enrolled in face-to-face LDs. This study has important implications for students as they uptake courses in online settings and faculty as they decide what portions of their courses to offer remotely.

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]

While cheminformatics skills necessary for dealing with an ever-increasing amount of chemical information are considered important for students pursuing STEM careers in the age of big data, many schools do not offer a cheminformatics course or alternative training opportunities. This paper presents the Cheminformatics Online Chemistry Course (OLCC), which is organized and run by the Committee on Computers in Chemical Education (CCCE) of the American Chemical Society (ACS)'s Division of Chemical Education (CHED). The Cheminformatics OLCC is a highly collaborative teaching project involving instructors at multiple schools who teamed up with external chemical information experts recruited across sectors, including government and industry. From 2015 to 2019, three Cheminformatics OLCCs were offered. In each program, the instructors at participating schools would meet face-to-face with the students of a class, while external content experts engaged through online discussions across campuses with both the instructors and students. All the material created in the course has been made available at the open education repositories of LibreTexts and CCCE Web sites for other institutions to adapt to their future needs.

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]

A modern undergraduate organic chemistry laboratory experiment involving the Suzuki-Miyaura coupling is reported. Although Suzuki-Miyaura couplings typically employ palladium catalysts in environmentally harmful solvents, this experiment features the use of inexpensive nickel catalysis, in addition to a "green" alcohol solvent. The experiment employs heterocyclic substrates, which are important pharmaceutical building blocks. Thus, this laboratory procedure exposes students to a variety of contemporary topics in organic chemistry, including transition metal-catalyzed cross-couplings, green chemistry, and the importance of heterocycles in drug discovery, none of which are well represented in typical undergraduate organic chemistry curricula. The experimental protocol uses commercially available reagents and is useful in both organic and inorganic instructional laboratories.

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]

The LIPID MAPS-Nature Lipidomics Gateway is a free, comprehensive online resource providing tutorials and instructional material, experimental data for lipids and genes along with protocols and standards, databases of lipid structures and lipid-associated genes or proteins, and a variety of lipidomics tools.

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]

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]

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]

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]

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]

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]

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]

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]

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]

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 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]

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]

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]

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]

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]

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]

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]

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]