The substitution of carbonyl compounds with liquid bromine as a brominating agent is the most commonly employed synthesis method for a-bromoacetophenone and its derivatives. However, liquid bromine possesses certain drawbacks, such as volatilization, high toxicity, strong corrosion, and poor reaction selectivity, which limit its application and…

Many undergraduate chemistry and biochemistry students pursue careers in healthcare. Biomaterials, designed to harmonize with the complexity of the human body, have become increasingly significant in medicine as implants, drug delivery vehicles and tissue scaffolds. We believe it is essential that undergraduates are exposed to biomaterial…

A set of inexpensive and pedagogically rich experiments focusing on S[subscript N]1, E1, and E2 reactions have been updated to include modern computational and spectroscopic analyses. The S[subscript N]1 experiment involves treatment of "tert"-amyl alcohol with hydrochloric acid to generate the corresponding alkyl chloride, which is used…

In this guided-inquiry lesson, students were tasked with determining the efficacy of an at-home drinking water filter at removing lead (Pb) from tap water using graphite furnace atomic absorption spectroscopy by determining the concentration of lead before and after filtration. The lesson was structured to allow students to choose and perform…

Transcription is the critical first step in expressing a gene, during which an RNA polymerase (RNAP) synthesizes an RNA copy of one strand of the DNA that encodes a gene. Here we describe a laboratory experiment that uses a single assay to probe two important steps in transcription: (1) RNAP binding to DNA, and (2) the transcriptional activity of…

The presented article is dedicated to a new way of teaching substitution in algebra. In order to effectively master the subject matter, it is necessary for students to perceive the equal sign equivalently, to learn to manipulate expressions as objects, and to perceive and use transformations based on defining their own equivalences. According to…

The design and analysis of experiments (DOE) has historically been an important part of an education in statistics, and with the increasing complexity of modern production processes and the advent of large-scale online experiments, it continues to be highly relevant. In this article, we provide an extensive review of the literature on DOE…

An activity is described that uses simple materials and an easy-to-perform protocol to estimate the Curie temperature of nickel, which is the temperature at which nickel loses its ferromagnetism. To do so, an object made of nickel metal is heated with a lighter until it loses its ferromagnetism. The metal is allowed to drop into a beaker that…

Performing HPLC-based experiments in the undergraduate practical classroom is difficult because of the time required to perform an analysis. This limits the type of practical to one that undertakes a simple quantitative analysis. However, with the use of sophisticated simulators, such as the one employed in this exercise, more complex experiments…

A standard problem for physics students is to calculate or measure the acceleration of an object down an inclined plane. Additional information can be obtained by measuring the angular acceleration as well as the linear acceleration. An experiment is described where a billiard ball was filmed as it rolled down an inclined plane at different…

Enzymes are nature's catalysts, mediating chemical processes in living systems. The study of enzyme function and mechanism includes defining the maximum catalytic rate and affinity for substrate/s (among other factors), referred to as enzyme kinetics. Enzyme kinetics is a staple of biochemistry curricula and other disciplines, from molecular and…

The Ouchterlony double immunodiffusion technique is used as a teaching tool for studying immune responses and exemplifying differences in antigen-antibody reactions. Although commonplace in undergraduate labs, standardized commercial kits limit learning experiences because they have fixed modalities of use, a low shelf-life, and impose budgetary…

In chemistry, a eutectic mixture refers to a mixture of two or more components at which the lowest possible freezing point is observed. This phenomenon is covered in a wide range of curricula such as physics, chemistry, chemical engineering, and pharmacy to various depths. Despite the significance of this phenomenon in pharmaceutical compounding…

An experimental design by combining hydrogel and ethylenediaminetetraacetic acid disodium salt (EDTA) for visually displaying chemical complexation reactions is developed. The Na[superscript +] ions on the [alpha]-l-guluronic acid (G) unit of the sodium alginate molecule undergo an ion exchange with a divalent cation, so that the G units are…

Polymer chemistry lab experiments present a unique opportunity to allow students to experience the consequences of reaction mechanisms on the properties of the resulting product. In this organic chemistry experiment, students prepared a polyamide by three different reaction mechanisms that represent step-growth and chain-growth methods of…