This paper describes an innovative, new, laboratory experiment conceived as a Senior Capstone Project by the student authors to provide experience with heat pipes for students in our junior-year Process Laboratory course at the University of Utah. Heat pipes can transport energy over long distances with minimal temperature gradients and no moving…

Tofu, a traditional Chinese food, is now popular worldwide. However, few people notice the chemistry that is involved in its production. To shed light on this, we have designed a simple demonstration for lower-level undergraduates in organic chemistry or biochemistry courses to help them understand the chemistry principles that underlie the…

Spin crossover (SCO) materials that switch between two different spin states, that is, the high spin (HS) and the low spin (LS) state, with very different optical, magnetic, and structural properties offer a unique platform to understand the consequences induced by the different electronic configurations of transition metal complexes. Due to the…

Frozen peas and carrots are commonly available in grocery stores in the United States. The carrots are cut into cubes roughly 8 mm on a side, while the peas are roughly spherical with a diameter of about 6 mm. They are prepared together in water that is brought to a boil. The peas and carrots, which are initially mixed together, separate as the…

Calorimetry is a central concept in the first semester general chemistry curriculum, and constant pressure (coffee-cup) calorimetry is a common experiment in the laboratory. However, constant volume (bomb) calorimetry is traditionally reserved for the physical chemistry laboratory. This article describes the advantages of incorporating bomb…

Why do we need to pour less water in an egg steamer to prepare more eggs to the same degree of 'doneness'? We discuss the physical processes at work in the electric egg steamer and resolve this seeming paradox. We demonstrate that the main heat transfer mechanism from steam to egg is due to latent heat through condensation. This not only explains…

The necessity to teach experimental physics in the pandemic period motivated the development of practices in which students may take measurements with instruments constructed by themselves. In this article, we present an experimental practice to approach Newton's law of cooling with a thermoscope (the earliest device for detecting changes in…

In this paper a well-known experiment is considered that is used to demonstrate some aspects of water boiling. It is shown that the currently popular explanation is wrong and a better explanation is proposed, backed up with experimental data. Variations of the experiment are proposed that can be used for a more in-depth examination of the…

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…

The Griess assay is widely used by regulation agencies as an official method for nitrite quantification in water and food samples. In Brazil, the official method, which has been used to determine nitrite in food, was described by Instituto Adolfo Lutz (283/IV) in 1984. It uses 8 mL of reactants and provides 50 mL (reactants plus sample) of waste…

An apparatus of the 70s for measuring thermal conductivity in different materials is used to visualize, through an infrared thermal imaging approach, temperature fields and the heat diffusion process. The observed temperature profiles also suggest solid grounds for a fair mathematical modelling of this phenomenon.

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…

A eutectic system is a mixture of two or more substances, displaying a melting temperature lower than its standalone components. The eutectic composition displays the lowest melting temperature of all mixtures. Typically, a eutectic system is used as an example of binary phase diagrams to demonstrate to undergraduate students. Herein, the liquidus…

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.

A newly developed laboratory learning program for high school chemistry courses is discussed, in which students discover the chemical mechanism governing exothermic phenomena during the reaction between a heating agent, namely, calcium oxide (CaO)--aluminum (Al) mixture, and water. Based on prior knowledge of simple heating agents such as CaO, the…