[dghughes]

>There was this amazing article in 2010 about "chemical compounds i will not work with". Tetrafluorohydrazine was one of them:

I remember reading that article it was interesting. But it's funny that hydrofluoric acid (HF) was not mentioned since it seems to be incredibly dangerous.

Periodic Videos on Youtube has a new video about hydrofluoric acid. Professor Martyn Poliakoff mentions HF is feared by people working in chemistry. He also said that even a small drop of HF on skin will cause a heart attack (and eat through your skin).

https://www.youtube.com/watch?v=6ZBwluyR2Tc

[bsder]

> He also said that even a small drop of HF on skin will cause a heart attack

I really wish people in the know wouldn't spread stuff like this.

HF isn't untreatably deadly like dimethylmercury.

HF is a strong acid and should be treated as such. Most effects of HF are quite treatable as long as you haven't managed to somehow convert it into elemental fluorine gas.

They key is that you have to know that you've had an HF incident.

What IS nasty is that an HF burn probably doesn't hurt until far too late. HF reacts with calcium and can inactivate pain neurons. And, while a small droplet won't do it, a large HF burn can cause a heart attack because it soaks up a lot of the free calcium in your bloodstream.

So, when you go in for treatment for an HF burn the doctor needs to start giving you calcium gluconate in order to resupply your calcium.

HF is nasty, but not so nasty that semiconductor fabs work terribly hard to get rid of it. Piranha etch (HF and HNO3 at 70C) is bog standard and people work with it every day.

Constrast this to Arsine gas (AsH3--flammable and toxic--oh, the joy!) which everybody works to get rid of.

[_0ffh]

Not just flammable but even pyrophoric! (re Arsine)

[youngtaff]

Hydrofluoric acid is nasty stuff that strips the calcium from your bones

My brother works in a oil refinery lab and had a HF acid escape.

Procedure for escape is jump in the lab shower, strip off and lather yourself with calcium based cream

Turning on the shower activates the lab alarm, and the medical and emergency crews turn up shortly after.

When things have settled there's a health and safety investigation / review of the incident.

[ncmncm]

Yet, you can buy it in 1% solution at your neighborhood hardware store.

Concentration matters.

[cr0sh]

I don't believe I've ever been in any hardware store that sold hydrofluoric acid in any concentration. Care to expand on what you meant?

Now - hydrochloric acid or sulfuric acid - both those (and some other relatively nasty chemicals) can be easily purchased at many hardware (and other) stores; the first is commonly known as "muriatic acid" (pool acid), while the second is sold (usually at auto parts stores, but there are some hardware stores that sell it too) for lead-acid battery "replenishment" (if the acid in them becomes too diluted from "topping up" with distilled water over time).

But HF? No - I certainly can't see where that would be allowed to be sold in any concentration to the ordinary public...

[detaro]

In low concentration, it's in various cleaning products, rust removers, that kind of thing. In some places, you can buy glass etching cream which also contains HF.

[ls612]

Dumb question from someone who knows very little chemistry; is it possible for a malicious actor to use some sort of distillation process to take that 1% solution and concentrate it into something much more dangerous?

[NickNameNick]

It's probably going to be more dangerous to the amature chemist than thier intended victim.

[dsfyu404ed]

Yes but it's way cheaper and easier to just use drain cleaner for those kinds of malicious things.

[dghughes]

The fun part in the video is when they neutralized the HF with sodium carbonate to make sodium fluoride which is used in toothpaste. Keeping in mind the concentration again.

[willis936]

HF is a weak acid and less dangerous than hydrochloric acid and sulfuric acid. If you really want bad news make piranha solution.

[dralley]

It's acidic, not less dangerous. If you get one of those other acids on you, you will know, immediately. Whereas HF will just absorb through your skin without appearing to cause any damage, but will kill all the tissue in it's path and start dissolving your bone underneath.

[mirimir]

Don't get it under your fingernails, however.

Or store it in a glass container.