An electric motor converts electrical energy into mechanical work and an electric generator converts mechanical work into electrical energy. The symmetry between the motor and generator naturally leads to questions about creating a perpetual motion machine. The allure of this question has inspired textbook problems, physics education articles, and…

A simple experimental setup using a smartphone and a pair of speakers is presented to perform an accurate experiment on interference of two point sources. The proposed experiment allows simple but interesting measurements to be done to introduce students to interference and diffraction phenomena. As such, the experiment effectively introduces the…

Under most conditions, a liquid mixture does not have long-range structural order and may be considered to be a homogeneous collection of molecules in random motion. However, if a single-phase critical mixture of a partially miscible liquid--liquid system is subjected to a small temperature jump into the two-phase region, then structural coherence…

Water electrolysis is used to teach important and fundamental concepts in chemistry. In practical water electrolysis experiments, it is difficult to achieve the ideal 2:1 ratio of hydrogen to oxygen. This work demonstrates an experimental setup comprising multiple water electrolysis cells connected in series to simultaneously visualize the effects…

As simple and ubiquitous redox-active organic molecules, quinones participate in diverse electron transfer processes in chemistry and biological systems for energy transformation and signal transduction. We introduce here a practical exercise to study the redox potentials of benzoquinone and its two derivatives by combining the electrochemistry…

The thermal equilibration of himic anhydride [IUPAC (2-"endo,"3-"endo")-bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic acid anhydride] to (2-"exo,"3-"exo")-bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic acid anhydride and subsequent recrystallization of the "exo"-product can be performed as a standard…

Already when they enter primary school, children have rich everyday experience with factors influencing the rate of liquids' evaporation. Tea spilled into a large puddle on the table evaporates more rapidly than the same amount remaining in the cup, laundry hanging on a clothesline dries faster on a hot and windy day in comparison with a cold and…

A hula hoop rotating around a person's waist is an example of circular motion where the centripetal force on the hoop is directed towards the centre of the circle rather than the centre of the hoop. The friction force on the hoop is relatively small by comparison since the hoop rolls around the waist. A slight complication is that the hoop rotates…

Generated information is better recognized and recalled than information that is read. This so-called "generation effect" has been replicated several times for different types of material, including texts. Perhaps the most influential demonstration was by McDaniel et al. (1986, "Journal of Memory and Language," 25, 645-656;…

In this supplement to our second-year supercapacitor lab (Bringing Real-World Energy-Storage Research into a Second-Year Physical-Chemistry Lab Using a MnO[subscript 2]-Based Supercapacitor. "J. Chem. Educ." 2018, 95 (11), 2028-2033), we incorporate a color indicator as indirect evidence for the manganese oxide's pseudocapacitive…

A six-laboratory session biofilm-focused biochemistry laboratory module is described. Through just six four-hour laboratory sessions over three weeks, students first master background knowledge and fundamental experimental techniques to explore questions involving bacterial biofilms at the interface of microbiology and biochemistry and then…

The study of gels and their properties is a compelling topic both technologically and scientifically, and should therefore be emphasized in chemistry and material science syllabuses. In the present laboratory experiment, we propose two experiences, aimed at introducing gelation and gel transport properties using silica gels made from sodium…

A laboratory exercise on the interaction between the herbicide pendimethalin (PM) and goat serum albumin (GSA), a carrier protein present in mammalian blood circulation, is described. Fluorescence spectroscopy was used to study the binding reaction between PM and GSA. Titration of a constant amount of the protein (GSA) with increasing ligand (PM)…

Next generation sequencing has revolutionized molecular biology and has provided a mechanism for rapid DNA and RNA sequence analysis. Yet, there are few resources to introduce next generation sequencing into the undergraduate biochemistry and molecular biology curriculum. Herein, we describe the design, execution, and assessment of a four-week…

The Hofmeister series is a recurring trend that ranks ions' abilities to influence various aqueous processes in solution. Herein, a set of project-based experiments was developed for students in an upper-level physical chemistry laboratory to investigate the specific ion effects on the thermodynamics of caffeine partitioning between aqueous and…