Although nuclear half-life is vital to physics and physical science, and to sensitive societal issues from nuclear waste to the age of the Earth, a true lab on half-life is almost never done at the college or high school level. Seldom are students able to use radioactivity to actually date when an object came into being, as is done in this…

A two-part experiment using bubble rafts to analyze amorphous structures is presented. In the first part, the distinctions between crystalline and vitreous structures are examined. In the second part, the interface between crystalline and amorphous regions is considered. Bubble rafts are easy to produce and provide excellent analogy to recent…

Enzyme kinetics is an essential part of a chemistry curriculum, especially for students interested in biomedical research or in health care fields. Though the concept is routinely performed in undergraduate chemistry/biochemistry classrooms using other spectroscopic methods, we provide an optimized approach that uses a real-time monitoring of the…

Fluorescent proteins are commonly used in cell biology to assess where proteins are within a cell as a function of time and provide insight into intracellular protein function. However, the usefulness of a fluorescent protein depends directly on the quantum yield. The quantum yield relates the efficiency at which a fluorescent molecule converts…

This series of three practical sessions centers on drugs that inhibit the enzyme acetylcholineesterase. This enzyme is responsible for the inactivation of acetylcholine and has been the target of drugs to treat glaucoma and Alzheimer's disease and for a number of insecticides and warfare agents. These sessions relate to a series of carbamate…

A multistep synthesis of 10-ethyl flavin was developed as an organic chemistry laboratory experiment for upper-division undergraduate students. Students synthesize 10-ethyl flavin as a bright yellow solid via a five-step sequence. The experiment introduces students to various hands-on experimental organic synthetic techniques, such as column…

Two introductory organic chemistry laboratory experiments are described based on the Diels-Alder reaction of 2,3,4,5-tetraphenylcyclopentadienone, which is synthesized prior to or in a one-pot reaction, with styrene. Students are presented with three possible products, the "endo" and "exo" diastereomers and the decarbonylated…

The transport of molecules across biological membranes are critical for most cellular processes. Membrane permeability is also a key determinant for drug absorption, distribution, and elimination. Diffusion, that is, the migration of matter down a concentration gradient, is a simple mechanism by which both endogenous and drug molecules can enter…

A laboratory experiment was developed to follow the gelation of a polyvinyl alcohol (PVA) solution upon addition of borax by using rotational viscometry. The rheological properties of the gel were examined, measuring the dependence of viscosity and shear stress on the shear rate. Time-dependent studies were also conducted in which the viscosity of…

The Characterization and Analysis of a Product (CAP) project is used to introduce first-semester general chemistry students to chemical instrumentation through the analysis of caffeine-containing beverage products. Some examples of these products have included coffee, tea, and energy drinks. Students perform at least three instrumental experiments…

In this paper, we describe an experiment for the undergraduate physical chemistry laboratory in which students determine the speed of sound in the gases He, N[subscript 2], CO[subscript 2], and CF[subscript 3]CH[subscript 2]F. The experimental apparatus consists of a closed acrylic tube containing the gas under study. White audio noise is injected…

With new K-12 national science standards emerging, there is an increased need for experiments that integrate engineering into the context of society. Here we describe a chemistry experiment that combines science and engineering principles while introducing basic polymer and green chemistry concepts. Using medical sutures as a platform for…

This study investigated whether or not lab type, traditional lab or virtual lab, influenced students' engagement. To measure student engagement six students were videoed over the course of an 18-week semester while conducting 10 lab experiments. To analyze student engagement, a systematic visual comparison in the tradition of single case research…

Saccharin (1,2-benzisothiazole-3-one 1,1-dioxide) is an artificial sweetener used in the food industry. It is a cheap and easily available organic compound that may be used in organic chemistry laboratory classes for the synthesis of related heterocyclic compounds and as a derivatizing agent. In this work, saccharin is used as a starting material…

The concept of wave-particle duality in quantum theory is difficult to grasp because it attributes particle-like properties to classical waves and wave-like properties to classical particles. There seems to be an inconsistency involved with the notion that particle-like or wave-like attributes depend on how you look at an entity. The concept comes…