In this guided inquiry experiment, students extract catecholase enzyme from apples to catalyze the oxidation of catechol. They follow the reaction using the UV--vis absorbance of the "p"-benzophenone produced to determine the Michaelis-Menten kinetic parameters. Students make selected experimental choices within a structured framework…

Cosmetic chemistry is a prevalent part of everyday life, but there are very few undergraduate laboratories that explore this topic. Here, we present a laboratory exercise in which students use fizzing bath tablets (better known as "bath bombs") to learn about introductory kinetics. Students created their own bath bombs by combining…

Oxygen reduction reaction (ORR),as a multielectron electrode reaction, is an important electrochemical reaction in the field of electrochemical energy storage systems. Herein, a new advanced electrochemical laboratory experiment is designed for undergraduates to master the preparation of oxygen reduction catalytic electrode. Students can use…

This lesson focuses specifically on teaching concepts of speed and its impact on energy, as well as providing a basic introduction to potential and kinetic energy to fourth-grade students. "Next Generation Science Standards" ("NGSS") 4-PS3-1 states that students should be able "to use evidence to construct an explanation…

The modeling of rates of biochemical reactions--fluxes--in metabolic networks is widely used for both basic biological research and biotechnological applications. A number of different modeling methods have been developed to estimate and predict fluxes, including kinetic and constraint-based (Metabolic Flux Analysis and flux balance analysis)…

We report on an investigation of student thinking about steady-state pipe flow of an incompressible fluid. About 250 undergraduate engineering students were given a test consisting of two hydrodynamics questions, combining multiple-choice format with subsequent open-ended explanations. There is substantial evidence that students have difficulty…

The effects of kinetic vs thermodynamic control on "endo"/"exo" stereoisomer ratios can be observed in a simple Diels-Alder reaction between "N"-phenylmaleimide and furan. The use of microwave-promoted synthesis affords the cycloadducts in yields ranging from 65-100%, employing reaction times of 1-10 min at…

A physical chemistry lab for undergraduate students described in this report is about applying kinetic models to analyze the spread of COVID-19 in the United States and obtain the reproduction numbers. The susceptible-infectious-recovery (SIR) model and the SIR-vaccinated (SIRV) model are explained to the students and are used to analyze the…

Quantitative demonstration of chemical kinetics often requires sophisticated equipment and materials. By using inexpensive and commonly available chemicals, we propose here two clock reactions, oxygen-safranin-benzoin clock and cysteine-iodine-hydrogen peroxide clock. Students simply measure and add stock solutions to start clock reactions. Sudden…

Work, kinetic energy (KE), and potential energy (PE) are key physics concepts, taught in essentially every introductory physics course along with the physical laws such as the work-kinetic energy theorem and the conservation of mechanical energy, which describe how the values of those quantities change during various processes. Quite appropriately…

A laboratory experiment is described in which students carry out immobilization of the enzyme invertase via entrapment in alginate (Ca-alginate) and, accordingly, estimate values for kinetic constants and mass transfer coefficients. Immobilization of enzymes, or confinement thereof to a defined space with retention of most catalytic activity, is…

We present an algorithm for solving the time-dependent Schrödinger equation that is based on the finite-difference expression of the kinetic energy operator. Students who have some knowledge of linear algebra can understand the theory used to derive the algorithm. This is because the finite-difference kinetic energy matrix and the Hückel matrix…

The principles of chemical kinetics comprise one of the core topics that appear throughout chemistry. Standard kinetics lessons typically cover reaction rates and relative rates, rate laws, integrated rate laws, half-lives, collision theory, and the Arrhenius equation. They can also introduce a discussion of mechanisms as well, which may be the…

What if "every breath you take, every move you make" (Sting 1983) could be harnessed to produce renewable energy? Triboelectric nanogenerators (TENGs) are state-of-the-art devices researchers are studying to do just that--convert kinetic energy into electrical energy at the source (Saurabh Rathore 2018). This type of electrical energy is…

Experimental results are presented on the collision of a superball with two different wood blocks. The results are in reasonable agreement with a simple collision model where kinetic energy is conserved, but better agreement is obtained if a small loss of kinetic energy is assumed, as observed. The physics is slightly more complicated than the…