Hydrofluoric frickin' acid

My students often ask me what the most dangerous chemical that we have in the storeroom at school is. I don't have any clue, I'll admit. Methanol is pretty dangerous because its flash point is so low and because it evaporates so easily and quickly. Sulfuric acid is also pretty rough stuff in its concentrated form. There's also the chunks of sodium that we have. It's all pretty dangerous.

But then there's hydrofluoric acid.

We don't have any, but I'm terrifically thankful for that, 'cause it's some nasty stuff. Check this from a Discover magazine article about a man who spilled hydrofluoric acid on himself a few years back...

At the back of a dusty shelf stood a small bottle labeled Industrial Laundry Rust remover. The side of the bottle carried the warning CAUTION: DO NOT USE WITHOUT GLOVES. William didn’t read that bit, however, and he removed the cap from the bottle, spilled some liquid onto a rag, and began rubbing it into his stained coat. But as the stain began to fade, his right hand, the hand he was using to apply the liquid, began to hurt. After 20 minutes the pain was so intense that he had to stop. Within 40 minutes he could no longer move his fingers. Frightened and in terrible pain, he managed to drive himself to our emergency room.

I know places where I could buy hydrofluoric acid, man.

That stuff scares the crap out ofme.