The classroom jumping ring demonstration is nearly always performed using alternating current (AC), in which the ring jumps or flies off the extended iron core when the switch is closed. The ring jumps higher when cooled with liquid nitrogen (LN2). We have performed experiments using DC to power the solenoid and find similarities and significant…

FlashPhotol is an educational software package that introduces students to the kinetics of transient species and fast reactions. This is achieved by means of a computer-simulated flash photolysis apparatus that comprises all major functional elements and that students can use to perform various experiments. The experimental interface presents a…

An inexpensive enzyme kinetics laboratory exercise for undergraduate biochemistry students is described utilizing tyrosinase from white button mushrooms. The exercise can be completed in one or two three-hour lab sessions. The optimal amounts of enzyme, substrate (catechol), and inhibitor (kojic acid) are first determined, and then kinetic data is…

In high-school teaching of mechanics, we deal, among other things, with the nature of static and kinetic friction, forces that are proportional to the normal force. Under the influence of frictional forces, a body moves down a rough sloped decline at a fixed rate of acceleration that is independent of its mass. This situation does not apply to…

Recently there has been a renewed interest in the development and use of pedagogical games, as they provide an interesting approach to the appropriation of knowledge in the context of active learning. However, most didactic games fail to completely implement a cycle of reflection and action, thereby fostering mostly lower-order thinking skills and…

Science students need exposure to activities that will help them to become familiar with phenomena exhibiting exponential decay. This paper describes an experiment that allows students to determine the rate of thermal energy loss by a hot object to its surroundings. It requires limited equipment, is safe, and gives reasonable results. Students…

Acquiring conceptual understanding seems to be one of the main challenges students face when studying organic chemistry. Traditionally, organic chemistry presents an extensive variety of chemical transformations, which often lead students to recall an organic transformation rather than apply conceptual knowledge. Strong surface level focus and…

Newton's first and second laws have implications for the kinetic energy as well as the momentum of a body. It is recommended that this should be made explicit at an appropriate point in a course.

Kinetic energy and momentum are indispensable dynamical quantities in both the special theory of relativity and in classical mechanics. Although momentum and kinetic energy are central to understanding dynamics, the differences between their relativistic and classical notions have not always received adequate treatment in undergraduate teaching.…

An effective way of teaching undergraduates a full complement of research skills is through a multiweek advanced laboratory experiment. Here we outline a comprehensive set of experiments adapted from current primary literature focusing on organic and inorganic synthesis, catalysis, reactivity, and reaction kinetics. The catalyst,…

An experimental protocol that provides an excellent way to discuss concepts at the crossroads of organic chemistry and biochemistry employing biocatalysis is presented. By evaluating several reaction parameters (enzyme source, organic solvent, and acyl donor), it was possible to conduct an enzymatic kinetic resolution experiment using…

We propose the use of a smartphone based time-lapse and slow-motion video techniques together with tracking analysis as valuable tools for investigating thermal processes such as the response time of a thermometer. The two simple experimental activities presented here, suitable also for high school and undergraduate students, allow one to measure…

As the need for alternative energy becomes increasingly important, energy research and related industries are rapidly expanding. This lab incorporates current energy-storage research into a second-year lab that instills real-world, industry-relevant knowledge and skills while teaching and reinforcing physical-chemistry concepts. A manganese oxide…

Determination of enzymatic activity is a relevant experiment in teaching chemistry and biochemistry to high school and college students. A method for measuring the kinetic parameters of lactose cleavage by the enzyme lactase is described. This enzyme catalyzes the hydrolysis of lactose to galactose and glucose. The kinetic parameters can be…

The oxidation of iron is an important reaction due to its high economic impact. In this laboratory exploration, the total order of this reaction was determined using commercially available handwarmer packets that rely on the iron-oxygen reaction to generate heat. The active ingredient in the handwarmer packet is iron, which interacts with…