There are barriers to reaction ("Skeletal chemistry" 8 of 9)
"The world is sinking into chaos, but the existence of barriers to reaction means that collapse does not occur in a flash. Barriers slow the collapse, allowing the world to discover different ways of fulfilling its destiny."
Kool Colors
The Kool-Aid label says "Do not store in metal container" since dyes in the drink will react with metal. Putting steel wool in Kool-Aid gets the reaction going, and this experiment allows varying the temperature, surface area, and concentration of the reaction to see how the reaction rate changes.
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Heat Speeds Up Reactions
This activity starts with a kinesthetic model: "Move like a molecule at high temperature (you should run). Move like a molecule at low temperature (you should move slowly)." It is followed with a paper model of molecules colliding at different speeds, then an experiment using a glow stick in hot and cold water to see how the light output (and hence the reaction rate) changes. The first two parts are useful models, even without cracking a glow stick.
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"Skeletal chemistry" article
This is one of the nine central ideas that Peter Atkins lays out in his 2005 article, "Skeletal chemistry." Each of the other ideas has its own list in SMILE.