demonstrations

Expanding on Self-Inflating Balloons: Activities Involving Moles, Gas Laws, and Thermochemistry

Dean Campbell | Thu, 02/10/2022 - 08:42

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Balloons that inflate using carbon dioxide produced from the reaction of citric acid and sodium hydrogen carbonate can be used to demonstrate a number of aspects of chemistry. Gas laws were used with the balloons to illustrate limiting reactants, molar mass of gases, and rockets. The endothermic reaction in the balloon was visualized with an infrared camera, and the Green Chemistry aspects of these balloons were considered.

Solution to Chemical Mystery #19: Multi-colored Mixture

Tom Kuntzleman | Sun, 02/06/2022 - 13:22

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Did you figure out how to create a multi-colored mixture? Check out the solution to Chemical Mystery #19: Multi-colored Mixture!

Chemical Mystery #19: Multi-colored Mixture

Tom Kuntzleman | Mon, 01/31/2022 - 16:06

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Can you use your knowledge of chemistry to figure out what is going on in Chemical Mystery #19?

A Demo A Day: Demonstrations and Props Used in My General Chemistry Class

Dean Campbell | Mon, 01/17/2022 - 17:43

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This blog post includes short descriptions of demonstrations and props that Dean Campbell has used while teaching his collegiate General Chemistry I course.

Generating explosive gases from sand

Tom Kuntzleman | Fri, 01/07/2022 - 12:16

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Did you know that sand can be converted into a mixture of gases that spontaneously ignites in air? The procedures involved are relatively simple to perform, spectacular to observe, and relate to a rich assortment of chemical principles.

Food Dyes as Acid-Base Indicators

Tom Kuntzleman | Sun, 11/28/2021 - 10:51

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Natural food dyes are being sold online and in stores that can be used as acid-base indicators. These dyes open up a host of possibilities for at-home and in-class. For example, these food dyes can be used as indicators in the quantitative titration of the Mg(OH)₂ in milk of magnesia.

Freezing Point Depression Near Body Temperature with Eicosane and Azobenzene

Dean Campbell | Tue, 11/02/2021 - 11:20

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Addition of a small amount of azobenzene to eicosane can lower its melting point to where it can be melted by body heat. This can be used in demonstrations and classroom activities related to freezing point depression and phase diagrams.

Thermal Paper as a Polarity and Acidity Detector

Dean Campbell | Thu, 10/28/2021 - 14:09

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Thermal paper such as that used for point of sale receipts typically functions by darkening when exposed to heat. The pigment system used in this paper also darkens when exposed to solvents of intermediate polarity and acids. This enables thermal paper to be used as an inexpensive sort of indicator paper for a variety of demonstrations.

Lithium Battery Flame

Tom Kuntzleman | Mon, 09/27/2021 - 16:42

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Inspired by a recent article in the Journal of Chemical Education, Tom Kuntzleman attempted to extract lithium from a coin battery, and to use the extracted lithium to produce a pink flame.

Recreating the Mary Poppins Colored Medicine Scene with Acid-Base Indicators

Nick Thomas | Mon, 09/27/2021 - 13:21

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When introducing acid-base theory, the concept of indicators and their pH color changes is usually discussed. To illustrate some color transitions to students, a classroom demonstration has been devised based on a memorable scene from Disney’s 1964 movie Mary Poppins.