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Chemical Activities Involving Reversible Thermochromic Pigments

Dean Campbell | Wed, 08/16/2023 - 07:17

The color of a thermochromic system depends on its temperature. The colors of leuco dye-based systems can also be influenced by adding acids or bases to the thermochromic reactions. These can be used to create colorful demonstrations of acid-base chemistry. Thermochromism found in color changing cups can also be used to visualize heat flow, and therefore thermodynamic principles, associated with stretching and contracting elastomers.

Algae Connections to Chemistry Classrooms

Dean Campbell | Fri, 03/31/2023 - 09:55

This timely post is a perfect fit for the theme of Chemists Celebrate Earth Week 2023! Algae is a rich topic with many possible connections to the chemistry classroom. Algae needs to take in light, carbon dioxide, and various simple nutrients and, though it can sometimes get out of control, can produce oxygen, diatomaceous earth, and other products. It can even fluoresce pink! 

Laser-Cutting CDs into Snowflakes

Dean Campbell | Wed, 03/08/2023 - 15:57

Laser cutters can be used to cut and engrave a variety of thin materials. Compact discs, composed of layers of polycarbonate plastic and aluminum metal, were explored for their ability to be shaped with a laser cutter. The laser can successfully cut and engrave the compact discs into the shape of snowflake. However, each disc must first be coated with a material like glue in order to protect the plastic from discoloration and the byproducts from cutting the plastic that can accumulate on the disc surface.  

Hatching Ideas to use Egg Cartons to Represent Electron Arrangements

Dean Campbell | Mon, 01/23/2023 - 14:11

Egg cartons and small objects such as milk jug caps or plastic eggs can be used to illustrate chemical concepts. The egg cartons can be cut into trays to represent atoms or to represent energy levels associated with atomic orbitals. The plastic caps or eggs distributed among the dimples of the trays can be used to represent electrons or pairs of electrons.

Finding Flash Rocks

Dean Campbell | Sat, 08/13/2022 - 10:20

Flash rocks were discussed in a previous post as stones made of quartz that produce light by triboluminescence when struck together. This post provides some description of their origins and tips on how to find them, making connections to some of their properties.

Paper Snowflakes to Model Flat Symmetrical Molecules

Dean Campbell | Wed, 04/06/2022 - 13:39

Flat, symmetrical molecules can be modeled by folding a sheet of paper, cutting patterns into the folded structure, and unfolding to produce the flat paper models. The finished models resemble paper snowflakes, but have a variety of rotational symmetries. Template patterns for several molecules are available for download in the Supporting Information.