I’m not a chemist, but I recently came across the blog of pharmaceutical chemist Derek Lowe, and in particular, his serial feature called Things I Won’t Work With. In it, he details with anecdotes, references and his own superb wit various chemicals that, because they are extremely toxic, volatile, or otherwise dangerous, he won’t ever work with in the lab. I encourage you to read the posts, but I’ll leave you with a few choice quotes that made me laugh:

On dioxygen difluoride:

Hydrogen sulfide, for example, reacts with four molecules of FOOF to give sulfur hexafluoride, 2 molecules of HF and four oxygens . . . and 433 kcal, which is the kind of every-man-for-himself exotherm that you want to avoid at all cost. The sulfur chemistry of FOOF remains unexplored, so if you feel like whipping up a batch of Satan’s kimchi, go right ahead.

For reference, 433 kcal (per mol) is the equivalent of almost a half-kilo of TNT. Yikes.

On azidotetrazolate salts:

These Bavarian rowdies have prepared a series of salts of the unnerving azidotetrazolate anion. As they point out, the anion was described back in 1939 (in what I hope was a coincidental association with the outbreak of the Second World War), but its salts are “rarely described in the literature”. Yes indeed! People rarely spray hungry mountain lions with Worcestershire sauce, either, come to think of it.

On chlorine trifluoride:

There’s a report from the early 1950s […] of a one-ton spill of the stuff. It burned its way through a foot of concrete floor and chewed up another meter of sand and gravel beneath, completing a day that I’m sure no one involved ever forgot. That process, I should add, would necessarily have been accompanied by copious amounts of horribly toxic and corrosive by-products: it’s bad enough when your reagent ignites wet sand, but the clouds of hot hydrofluoric acid are your special door prize if you’re foolhardy enough to hang around and watch the fireworks.