Lest we forget the corrosive strength of sulfuric acid

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Why did spongey have to be smiling? That’s just mean.


Apparently hydrofluoric acid is worse.

As a high school student I assisted my chemistry teacher when he was one of the judges for a science fair in the elementary school next door.

One of the students had an experiment that involved etching some small metal plates. He poured some hydrofluoric acid that his father had provided on them. No gloves, no safety equipment.

I heard a “squeak” from the teacher, and observed him turning white, then red.

If the kid had a control, it would have been the best experiment of the fair.


Johnny was a chemist
But Johnny is no more
For what he thought was H20
Was H2SO4


Hydrofluoric is less dramatic in terms of sheer displays of acidic power(except that it will attack glass pretty enthusiastically, which few of its peers can handle); but it has the excitingly ghastly power of ‘soaking into your skin and grabbing all the calcium it can get its hands on’. Since most people are rather attached to their skeletons, and consider the various calcium-channel cellular mechanisms to be life critical; this can go poorly.

Sulfuric is more of a ‘straight, old school, chemical burns’ sort.


Sulfuric acid used to be called “oil of vitriol” because you could get it by heating vitriol, a glassy rock made of a number of different metallic sulfate. Vitriol of argile is an old name for aluminum sulfate, or alum for instance. You heat vitriol, it exudes an oily liquid – sulfuric acid, or at least, something with pretty high concentrations of sulfuric acid.

It was only later that “vitriolic” came to mean bitter, nasty, etc, after the effects of sulfuric acid. Sulfuric acid wasn’t called “vitriol” because it was mean, being mean was called vitriolic to remind one of the effects of H2SO4.


Cool video, but the lack of safety equipment gives me the fantods, and I’m not even my high school chemistry teacher. She’d’ve straight up flunked any student who did that.


Oh yes. Pouring conc. Sulphuric straight out of a large bottle onto some non-lab equipment, using no safety equipment whatsoever is a recipe for chemical burns.

Interestingly,the sponge is disintegrating leaving behind that back residue because the acid is ripping the structure of the polymer apart, leaving you with a mush of (rather hot) carbon. This is what it will do to any carbon rich substance, such as cloth. and its dehydrating powers will work well on anything containing a lot of water, such as human skin.


Cool… Now try it with this

/Just not when I’m around…


Um, gloves???


I think it depends on the substrate-- hydrofluoric acid is “worse” because it will etch glass (normally impervious to other acids), and because it reacts withthe human body in a particularly nasty way. But HF is also known as a weak acid-- unlike hydrochloric, nitric, sulfuric, perchloric, hydrobromic, hydroiodic and chloric acids.


Or maybe some FOOF?


I liked the soundtrack, but I was disappointed there were no Peeps.


And we’ve been doing this to our environment for hundreds of years…ah, chemicals, aka alchemy, you wily destructive devils of industry, always seeking gold…

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Precisely why it’s my go-to drain cleaner; nothing clears hair and veggie waste better (well, nothing that’s relatively safe; -) Just make sure it doesn’t touch fixture finishes or grout… Chase it with some boiling water and that clog is gone!

Also used as tray cleaner in photo processors for removing silver. Although these days, “progress” – most tray cleaner now comes with a dye to mark spills/slops. The dye is wicked permanent, and somewhat more of a pain to deal with than just straight acid.

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You lost me a “lest”…

Saw this in the shops recently… is it any good?


I wouldn’t mind to see it.

Too bad that today’s rocket propellant research isn’t what it used to be.


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…there’s one youtube video of ClF3. Enjoy!