Recent space-related phenomena like aurora and a comet were viewed by large numbers of people. These phenomena can be connected to concepts described in chemistry courses, such as electronic structures and light emission associated with species such as excited oxygen atoms.
When iron spheres at room temperature are added to liquid nitrogen, the nitrogen boils as heat is transferred in from the iron. The amount of liquid nitrogen boiled depends on the amount of heat transferred, which depends on the mass of the iron added. However, the rate at which liquid nitrogen boils depends on the surface area of the iron in contact with the liquid nitrogen. These phenomena can be studied with experiments which measure the mass lost by the boiling liquid nitrogen.
Pharaoh's serpent is the name of a very interesting chemical reaction that produces a snake-like foam. Unfortunately, it requires the use of a toxic mercury compound. Explore this very similar reaction that can be achieved quite simply by using fuel tablets and calcium gluconate tablets and learn a lot about the chemistry that is involved!
This activity allows for the simple and accurate determination of the heat of fusion, ΔHfusion, of water at 0°C.
Josh Kenney shares three simple and inexpensive demonstrations using Elmer’s glue.
A trip to see the 2024 solar eclipse provided the opportunity to explore ideas associated with sulfur in petroleum, sunlight intensity measurements, laser interference patterns from eclipse glasses, and large-scale light emission from excited hydrogen.
This activity allows for the simple and accurate determination of the heat of vaporization, ΔHvap, of water at 100°C, and ultimately the approximate strength of a hydrogen bond in boiling water, in kJ·mol–1.
In a classic demonstration of energy conservation, smashing two large steel ball bearings generates sufficient heat to burn a hole through a piece of paper. Josh Kenney found this demonstration underwhelming because the paper doesn't look burned. So, he upgraded the experiment by covering the paper in Elmer's Color Changing Glue. Now, a spectacular color change reveals the increase in heat!
Flash rocks, typically pieces of quartz that produce light when struck together, are an example of the complex phenomenon of triboluminescence. The green chemistry aspects for the flash rock demonstration are considered, and LEGO models illustrating quartz crystals, piezoelectric materials, and nonpiezoelectric materials are presented.
The reaction of hydrogen and oxygen gases to form water is well known to be an exothermic reaction. That reaction can occur by first absorbing the hydrogen into palladium metal, and then placing the resulting palladium hydride into contact with oxygen in the air. Infrared and visible light videos were recorded for this process involving palladium foil, and the Green Chemistry and safety aspects of these activities are considered.
