We present a thermodynamics experiment suitable for first year undergraduate students employing Stirling Engines to create a demonstration of energy transformation and to measure the mechanical efficiency of such engines. Using an inexpensive transparent chambered Stirling Engine, students can connect concepts such as the theoretical…

The anomalous thermal expansion of water in the 0 °C-4 °C range is extremely important to life on Earth, but it is normally not presented experimentally in educational settings. This paper presents a simple experiment to explore the anomalous thermal expansion of water in the 0 °C-4 °C range and the heat exchange processes in natural bodies of…

Millions of people do not have access to clean drinking water; thus, cost-efficient water treatment systems are vital. Chemists, environmentalists, technicians, and engineers will be the professionals making breakthroughs in this industry. This laboratory experiment aims to introduce undergraduate students to the removal of pollutants from water…

Heat transfer is a phenomenon well known from everyday life. It is intuitively connected to the properties of materials, that is, to the physics concept of thermal conductivity relevant for cooking or maintaining the constant temperature in rooms, even without being familiar to the underlying physics. However, measurement of thermal conductivity…

Keto-enol tautomerism is a fundamental concept that examines the migration of a proton between two constitutional isomers, the keto and enol tautomer. Many experiments have been proposed to understand the concept behind Meyer's Rule, which states that the keto tautomer is favored as the solvent polarity increases. However, all the experiments have…

Physics and chemistry students learn several methods to determine the density of materials. While measuring the mass of materials is usually simple, volume measurements are more complex. For simple shapes the volume may be determined by measuring its geometry; for more complex shapes students often use Archimedes' principle. However, neither of…

This paper reports the development and application of a low-cost multifunctional webcam spectrophotometer for the conduct of molecular absorption and fluorometric measurements. The equipment, which costs approximately US$20 to be fabricated, consists of a webcam, a diffraction grating, and a slit, all positioned inside an MDF box. Spectral…

When we teach thermodynamics, a vacuum container used to keep food isolated from air is a cheap and interesting teaching device. There are some experiments already described in the literature and we can also find videos of demonstrations on YouTube. At the same time, there is increasing interest in how to utilize smartphones in physics…

Iodonium zwitterions are hypervalent iodine compounds in which the iodine center binds to two substituents and carries a positive formal charge which is compensated by a negative charge within the same molecule. Under thermodynamic conditions, iodonium zwitterion sallow concerted nucleophilic aromatic substitutions to be performed, followed by…

The effects of kinetic vs thermodynamic control on "endo"/"exo" stereoisomer ratios can be observed in a simple Diels-Alder reaction between "N"-phenylmaleimide and furan. The use of microwave-promoted synthesis affords the cycloadducts in yields ranging from 65-100%, employing reaction times of 1-10 min at…

An easy operating tool has been developed for the quick measurement of thermoelectric power. The setup is made using a tweezer which consists of two circular copper plate electrodes. These copper electrodes are fixed to two arms of the tweezer which act as hot and cold probes. The setup has the very important advantage of easy sample mounting and…

Watching over a coffee maker in operation, and designing a simple experiment using it, invokes familiar and unfamiliar physical phenomena and techniques involving calorimetry and heat transfer.

This paper provides seven topics on sodium hydrogen carbonate (NaHCO[subscript 3]) and its ions for readers looking for familiar material phenomena to strengthen students' understanding of the chemical concepts of thermodynamics. The first concept is the ideal gas law, followed by the van't Hoff equation, Gibbs energy, pH change, chemical…

In this laboratory experiment, students apply a mass-based approach to determine the Henry's law constant for CO[subscript 2] using a small bottle of a diet carbonated beverage. The calculations are challenging; therefore, team-based learning is encouraged. Our students reported values of 0.033 ± 0.003 mol/(L[middle dot]atm) at room temperature…

A revised version of a traditional physical chemistry laboratory experiment has been developed to enhance student discussion in the laboratory and to improve students' connections between physical chemistry concepts and real molecular systems. In this experiment, students explore the keto-enol tautomerization of 2,4-pentanedione. However, unlike…