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The classic classroom or lab activity using coin flips to illustrate the first order kinetics of radioactive decay is connected to the tragedy of radiation exposure of workers at facilities using radium-containing luminescent paint. Some of the chemistry related to the contamination of these “radium girls” is explored, with connections being made to the Principles of Green Chemistry and the United Nations Sustainable Development Goals.
There are some simple ways to break chemical bonds with microscale techniques.
A new lesson that uses PES evidence to drive the instruction that would allow the students to identify the limitations of the Bohr model and introduce the Quantum Mechanical Model .
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.
Thin sheets of polystyrene can be patterned with permanent markers to represent repeating units of the polymer and then shrunk down in size using heat. The shrunken models of the repeating units can be connected with a string and then flipped into positions to demonstrate different types of polymer tacticity.
A simple demonstration for high school chemistry students is described which gives a plausible connection between electrons as waves and the shapes of the s and p orbitals. This demonstration may build a transition from electrons as particles to electrons as waves.
Here is a quick and easy yet powerful experiment for para and diamagnetism that helps to provide evidence for quantum numbers.
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 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.
While students usually do well with naming binary ionic compounds of fixed charge, many students struggle with naming ionic compounds that contain ions of variable charge. This activity uses a technique often found in humanities classes, a gallery walk, as a guided inquiry experience harnessing real-life applications of several sets of related compounds to address many common misconceptions and lead students to discover the meaning of the Roman numerals when naming and writing formulas for these compounds.