Fluorine is an interesting chemical - it's extremely reactive, and it explodes a lot (with the right circumstances).
It could be in your home, too! But in the less dangerous form, Teflon.
Fluorine's atomic number is 9.
Fluorine is incredibly reactive because its outermost electron shell has only a single hole in it, and it loves to pull any other electrons it can lay its hands on into said hole to form a fluoride ion. Due to its reactivity, fluorine clings like a mofo to practically any molecule you bond it to, a feature which makes Teflon (polytetrafluoroethylene) nicely slippery and unreactive. Drug companies like organofluorine chemistry because substituting a fluorine atom for a hydrogen atom does all kinds of nifty things; the chemical industry likes fluorine because it makes nasty things like uranium much easier to work with, and it can do neat tricks like making compounds with some of the heavier noble gases (krypton and xenon; possibly radon, but it doesn't seem like anyone would want to try that one because radon is radioactive). As a general rule, though, you don't really want to be anywhere near the stuff. Yes, there are certainly more unpleasant chemicals in the world, such as that transcendently nasty darling of mad scientists everywhere, chlorine trifluoride. But that's like saying that David Icke is crazier than Alex Jones — manifestly true, but …
Crazy cool facts
- It is a yellow gas that killed a lot of the people who tried to isolate it.
- It is so reactive that hydrofluoric acid (HF), if it gets into your bloodstream, will suck the calcium out of your bones into your bloodstream, screwing up your electrolyte balance.
- Fluorine, either free or as a fluoride ion in hydrofluoric acid, can dissolve glass – it is usually stored in flasks made of Teflon, which, by the way, is also made with fluorine.
- Three atoms of fluorine will combine with a single atom of chlorine (Chlorine trifluoride, ClF3) to demonstrate emphatically that there are things more entertainingly hazardous than fluorine gas.
- To top the one above, there is dioxygen difluoride, O2F2 or more evocatively FOOF.
Fluorine and conspiracy nuts
- Theodore Gray's Periodic Table Table entry on fluorine (including one of the scariest samples in his awesome collection, a quartz vial of fluorine gas)
- Things I Won't Work With: Sand Won't Save You This Time
- Things I Won't Work With: Chlorine Trifluoride: Some Empirical Findings ClF3 versus other matter
- For more horrifying details, visit http://what-if.xkcd.com/40/.
- Things I Won't Work With: Dioxygen Difluoride