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- By Patrick Di Justo Cette adresse email est protégée contre les robots des spammeurs, vous devez activer Javascript pour la voir.
- May 31, 2011 |
- 12:00 pm |
- Wired June 2011
Photo: Mitchell Feinberg
- Charcoal
Usually made of wood heated until it’s almost pure carbon. Pull the pin, and the fuse will set it smoldering: When combined with potassium nitrate, charcoal is easy to ignite. - Potassium nitrate
Aka saltpeter, it gives off great quantities of oxygen when it burns, feeding the fire. Plants need potassium and nitrogen, so KNO3 has been used in fertilizer for centuries. The stuff used to come from bat poop or livestock pee, but today it can be made from ammonia. - Silicon
As the potassium nitrate and charcoal burn, elemental silicon is converted into tiny droplets of 2,500-degree silicon dioxide (aka superhot glass), which then spatters onto the other ingredients and ignites them. - Sucrose
Fuel for the fire. Sugar melts at 370 degrees Fahrenheit, a relatively low temperature that heats and vaporizes the tear-making chemical without destroying it. An oxidizer will help keep combustion going. - Potassium chlorate
An oxidizer. When heated, KClO3 releases copious amounts of pure oxygen. It also breaks down into potassium chloride, which makes up some of the smoke from the grenade. - Magnesium carbonate
Potassium chlorate does not get along with acid (the mixture is explosive). This stuff, found in laxatives, fire extinguishers, and pool cue chalk, keeps pH levels slightly basic, neutralizing any acidic content caused by chemical impurities or moisture. When heated, it gives off CO2, further dispersing the tear gas. - O-Chlorobenzalmalononitrile
A lachrymator, meaning it produces tears. It also causes that burning sensation in the nose and throat and on the skin. As little as 4 milligrams per cubic meter will disperse unruly crowds. It’s believed that a lethal dose is around 25 grams per cubic meter. - Nitrocellulose
Some grades of nitrocellulose, like guncotton, are explosives. Others are lacquers that might provide the finish on, say, a vintage guitar. Here, low-nitrogen NC is used as a sticky binder to keep all the other ingredients homogeneously blended.
