A man brought his chemist friend to the bar for a drink with the other friends. When asked what he wanted, the chemist decided that since she's the designated driver, she'll order water. "I'll have some H20, please!" the chemist said, with the man replying "I'll have some H20 too!"
I love the sequel to that one, too.
Same set up.
... The first man orders H20
The second man says "why would you say that? It's incredibly pretentious, and you look like a jerk. Just order water."
The first man frowns and sulks because his murder plot has been foiled.
It's actually because "per" is used to denote the maximum "proportion" of an element. Compare "oxide", which is just one oxygen. "per-" is also used in chemistry in the sense of the Latin prefix "per-", which attaches to adjectives and verbs and such to convey the sense of "very" or "all the way". For example, sometimes we refer to molecules as being "perdeuterated" when all hydrogen atoms have been replaced with the heavy isotope deuterium.
Pfff U(IV)? More like U's a little bitch that can't add that weeny little O-O single bond. The only oxyuranium species worthy of entering my body are stripped of all valence electrons. Good ol peruranic acid, U(O)2(OH)2, that's the real quencher!
It will damage your skin and mucous membranes. Pure H2O is quite reactive and will drain minerals from the environment. If your body is such an environment, it will get minor damages.