This paper describes an experiment with two touching rotating disks, whose movement is followed by video analysis. Within the disks' movements, there are intervals with sliding and intervals without sliding, that is, intervals with frictional forces between the touching surfaces and intervals without it. This system configuration allows for…

Glyphosate (N-(phosphonomethyl)glycine) is the most widely used herbicide on earth. A simple assay to quantify glyphosate concentrations in environmental samples was developed as part of an interdisciplinary effort linking introductory laboratory courses in chemistry, biology, and microbiology. In this 3 h laboratory experiment, students used…

Proficiency with instrumental analysis via GC-MS is an important skill for chemistry students. The application of analytical techniques and fundamental theoretical principles to real-world problems can be valuable learning exercises for undergraduates which can also improve their analytical thinking skills. Xylitol is generally considered safe for…

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…

Polymer chemistry is an integral part of art conservation graduate training programs. The list of materials used by artists and artisans and by conservators is vast, with the majority being polymeric in nature. Conservators use an array of polymers as coatings, adhesives, fills, supports, and structures. Aside from the chemistry of these…

The study of buoyancy becomes very interesting when we measure the apparent weight of the body and the liquid vessel weight. In this paper, we propose an experimental apparatus that measures both the forces mentioned before as a function of the depth that a cylinder is sunk into the water. It is done using two load cells connected to an Arduino.…

Surface modification has been considered as a fundamental item in upper-division undergraduate and master courses. Thus, the development of experiments regarding processes and characterization of surface-modification phenomena is highly desired. In this article, we propose an electrochemical and computational study of widely used…

An interdisciplinary laboratory experiment was designed and carried out on the basis of the photo/electrochromism of N,N'-bis(cysteine)pyromellitic diimide (BCPD), suitable for organic chemistry laboratory I and physical chemistry laboratory II students. In the organic chemistry laboratory, students synthesized BCPD and studied its…

An integrated pair of experiments has been developed to introduce undergraduate students to the ways in which electrochemistry can complement conventional synthetic chemistry involving redox reactions. Students first use cyclic voltammetry and linear scan voltammetry to characterize and quantify the products of the reaction between…

A laboratory experiment is described in which students determine the concentration and speciation of iron in beer samples using cloud point extraction and absorbance spectroscopy. The basis of determination is the complexation between iron and 2-(5-bromo-2- pyridylazo)-5-diethylaminophenol (5-Br-PADAP) as a colorimetric reagent in an aqueous…

The convenient synthesis of dihydroberberine by the reduction of berberine is described as an experiment for an upper-division undergraduate organic chemistry laboratory course. Students obtained up to 74% yield of the desired pure product without the use of chromatographic techniques. The antimicrobial activities of both compounds against…

Lab-based learning is an essential part of any undergraduate chemistry curriculum as it incorporates necessary and required hands-on experiential learning. However, in response to the COVID-19 pandemic, many students are learning from home, rendering laboratory instruction a particular challenge. Options for educators include third party virtual…

Laboratory exercises for undergraduate biochemistry students are described in which changes in sugar content during fermentation of the trendy beverage kombucha are analyzed by three methods: thin layer chromatography, a 3,5-dinitrosalicylic acid assay, and a standard commercial blood glucose meter. Each of the three analyses can be completed in a…

In conventional e/m experiments performed in undergraduate laboratories, generally a simple mechanical ruler is used to measure the radius of the circular trajectory of the electrons. But, the measurement error in this technique is mostly big and varies from one student to another. As an alternative to a mechanical ruler, we proposed a more…

The cannon boring experiment of Count Rumford, where eight kilograms of water were boiled by metal on metal friction, is investigated. Consideration of this dramatic demonstration can enrich classroom discussions of calorimetry, units of measure, elements, and thermodynamics. A section pertaining to use of the article in the classroom appears…