Fireworks! at Chemical of the Week . Here is the introduction from that page: "Have you ever been to an aerial fireworks show at an amusement park, baseball game, Fourth of July celebration, or on New Year's Eve and wondered about how all the impressive colors and sounds are produced? People everywhere enjoy the fantastic explosions and the brilliant light displays of fireworks. However, these spectacles are much more than just a form of entertainment. Each firework launched into the sky is a precisely formed assembly of chemicals and fuel, carefully calibrated to produce a particular effect – a red chrysanthemum spray accompanied by a powerful explosion, or a blue strobe, for example. Understanding how the contents of a firework produce the impressive variety of colors, forms, and sound intensities requires only a simple understanding of chemical reactions." I found it from the page about Arsenic (a chemical every mystery/suspense writer eventually is curious about).