HF (Hydrofloric Acid)

I know that Hydrofloric acid is one of the most corrosive and dangerous substences around. However, due to the high electronegativity of Florine, shouldn’t it be extremely stable and non-reactive?

Fluorine wants to react with the alkalines and the alkalai earth metals, the more massive the better. As a result the F in HF will passively ignore its organic surroundings and absorb its way into the human body, but as soon as it comes into contact with calcium, as in bones, it’s bye-bye hydrogen and hello fused bone. Not cool.

The flouride ion isn’t the least bit corrosive, but it’s high electronegativity is what makes HF corrosive. The F[sup]-[/sup] ion is very stable, but in order to get it’s extra electron it must steal it from the hydrogen. This produces lots of the not-so-stable H[sup]+[/sup]. The proton is what causes the corrosiveness. If flourine wasn’t so greedy ,the hydrogen could share it’s electron with flourine and fewer H[sup]+[/sup] ions would be produced. As it is nearly all of the HF releases protons into the aqueous solution.

Eventhough HF is extremly corrosive, in all actuality HF is considered to be a weak acid. It’s dissocation factor is miniscule compared to sulfuric or hydrochloric acids. A note to the wise, stay as far away as possible from HF, this acid does horrid stuff to the human body.

The main disadvantage of dermal exposure to hydrofluoric acid is that it does not produce any immediate irritation beyond a tingling or rash. As da King said, only later, as it migrates down through your tissues to the calcium in your bones does it begin to burn. Definitely not nice. Few liquid etch applications use the full strength (49%) HF in an acid sink format, and these days the precautions are extensive. Upon even suspected exposure you are required to apply a alkalai paste to the suspected area.

The real winners were the hot acid etch bath stations. Hot, fuming red nitric acid and fuming sulphuric acid are the real carnivores. Nitric acid is astonishingly adept at dissolving protein bonds, like the ones in your flesh. They are called “fuming” because when you pour a beaker full of room temperature acid, the surface of the liquid will begin to “smoke” as its vapors recombine with moisture in the air.

The fuming red nitric was the most obscene of all, it looked like a rust colored draft of Hell’s own brew. For how it could literally dissolve your flesh, it lived up to its appearence.

I love stuff like this! Tell me more!

Some of the synthetic materials used in drive belts and the like in cars can release hydroflouric acid when burned.

Cars that have had fires in the engine bay are a problem that require sreious precautions and even if the fire is only fairly the car will not only be written off but may be scrapped witout any attempt made to recover any companents of value.