this post was submitted on 07 Aug 2023
382 points (91.7% liked)

Showerthoughts

28979 readers
147 users here now

A "Showerthought" is a simple term used to describe the thoughts that pop into your head while you're doing everyday things like taking a shower, driving, or just daydreaming. The best ones are thoughts that many people can relate to and they find something funny or interesting in regular stuff.

Rules

founded 1 year ago
MODERATORS
 

Fire is the rapid oxidation of a material. Water is 2 hydrogen and 1 oxygen. Every molecule is fully oxidized. It's also a common byproduct of fire. Therefore, you can't burn it, because it's already burnt

top 50 comments
sorted by: hot top controversial new old
[–] [email protected] 102 points 1 year ago (4 children)

Oh man... Wait until you hear about fires hot enough that if you put water on then, it breaks the water molecule and the hydrogen molecules cause an explosion.

Look up class D fires.

[–] [email protected] 47 points 1 year ago (4 children)

Furthermore, you can burn water with a strong enough oxidizer. Oxygen, despite lending its name to the word "oxidize", is not the best oxidizer out there. That belongs to things with fluorine in it. You can burn water with pure fluorine gas to produce hydrogen fluoride and oxygen.

Don't try this at home. Both fluorine and the resulting HF is deadky.

HF is itself a super nasty piece of work -- a deadly acid that seeps through your skin and kills you from the inside.

[–] [email protected] 14 points 1 year ago* (last edited 1 year ago) (2 children)

Or Chlorine Trifluoride. That's some "no way in hell" stuff right there.

[–] [email protected] 13 points 1 year ago

Isn't this the stuff that the fascists tried to weaonize in WWII, but it was too dangerous to handle and it, like, burnt down a concrete bunker or something?

[–] [email protected] 13 points 1 year ago* (last edited 1 year ago) (1 children)

The fun part about that: you can burn hydrogen with fluorine because fluorine is the best oxidizer; it's then deadly (and caustic) because hydrogen is not the best reducer - it's both an oxidizer and a reducer and, as a result, it's basically middle-of-the-road for both properties. Specifically, most metals are better. So the HF will happily drop its hydrogen for many metals to oxidize (fluoridate) them instead. Lead, iron, zinc, aluminum, magnesium, and lithium will each make a way more stable fluoride than does hydrogen.

In solution (say, if you inhale HF, it'll dissolve into the moisture in your lungs), it breaks apart into H⁺ and F⁻ ions - both of which are just straight-up electrochemically promiscuous. The pair'll run through your lungs breaking up organic bonds like couples at an orgy.

Even so, HF doesn't hold a candle in terms of danger (and oxidation potential) compared to fluorine peroxide / dioxygen difluoride / FOOF.

[–] [email protected] 2 points 1 year ago

That looks like even more fun than chlorine trifluoride

[–] [email protected] 5 points 1 year ago

There's always a lower energy state

[–] [email protected] 3 points 1 year ago

Flourine by itself is nothing compared to chlorine triflouride (CTF) though.

There were some ideas to use it in rockets, but, as John D. Clark put it:

It is, of course, extremely toxic, but that's the least of the problem. It is hypergolic with every known fuel, and so rapidly hypergolic that no ignition delay has ever been measured. It is also hypergolic with such things as cloth, wood, and test engineers, not to mention asbestos, sand, and water—with which it reacts explosively. It can be kept in some of the ordinary structural metals—steel, copper, aluminum, etc.—because of the formation of a thin film of insoluble metal fluoride that protects the bulk of the metal, just as the invisible coat of oxide on aluminum keeps it from burning up in the atmosphere. If, however, this coat is melted or scrubbed off, and has no chance to reform, the operator is confronted with the problem of coping with a metal-fluorine fire. For dealing with this situation, I have always recommended a good pair of running shoes.

There were a few successful test fires with a CTF rocket on the ground, but to avoid explosions they had go through an elaborate multiple hour long cleaning procedure, and it ended up being too expensive and dangerous.

[–] Scubus 7 points 1 year ago

Magnesium fire has entered the chat

[–] [email protected] 6 points 1 year ago (1 children)

Ah so it's hot enough to electrolyze water and then when the hydrogen and oxygen gas move out of that heat zone, they're still in a hot enough area to re-oxidize into water, burning the hydrogen. Neat.

[–] wheeldawg 1 points 1 year ago (1 children)

Nothing about this makes sense. Is it reoxidizing or burning?

[–] [email protected] 6 points 1 year ago

Yes.

Not only will metal fires break apart the water into oxygen and hydrogen, but they will consume the oxygen, as the metal oxide is a more stable energy state than is water. So you end up with a billow of hydrogen coming off the fire that mixes with the oxygen just above (because lighter gases rise) the oxygen-depleted zone of the fire, and it combusts there.

[–] [email protected] 5 points 1 year ago (1 children)

There was some other thread talking about invisible fire produced by burning a particular gas... imagine getting burned and not being able to identify the source

[–] [email protected] 7 points 1 year ago (1 children)

You’re probably referring to methanol fires! Commonly used as a fuel for things like F1 cars, iirc.

[–] ikapoz 1 points 1 year ago

Hydrogen fires have the same characteristic as i understand it

[–] [email protected] 83 points 1 year ago (3 children)

Reddit hasn't had a quality shower thought like this on the front page in years. Well done fediverse.

[–] [email protected] 6 points 1 year ago

Any time I tried to post a shower thought on Reddit it was deleted because it either was posted previously (at any point in time, even if it was years ago) or was posted somewhere else online, not just Reddit, also at any point in time.

Nuts.

[–] [email protected] 4 points 1 year ago (1 children)

I might actually have to subscribe. I'm so used to avoiding the "default subs"

[–] [email protected] 3 points 1 year ago

For what it's worth, half of them are essentially 'water is wet'. Although as far as thoughts in the shower go, I guess that's fairly reasonable.

[–] [email protected] 3 points 1 year ago

I've seen a few great ones lately, but I've also been seeing a ton from people who don't understand the concept very well. Things like "it's not nice to be mean to people" or "there are more countries in Asia than China, Japan, and South Korea." I can't really say much as I haven't posted anything myself, but c'mon people!

[–] [email protected] 31 points 1 year ago (1 children)

I guess that makes water Hydrogen rust...

[–] [email protected] 7 points 1 year ago

More like hydrogen ash

[–] [email protected] 19 points 1 year ago (1 children)

Water is also hydrogen and oxygen floating around in a sea where they are constantly switching partners. An orgy if you will.

[–] [email protected] 9 points 1 year ago

That's why you're called a seaman when you go out floating in the ocean.

[–] [email protected] 19 points 1 year ago (1 children)

Next time it snows, remember: you're being gently coated in stellar ash.

[–] [email protected] 5 points 1 year ago (1 children)
[–] [email protected] 6 points 1 year ago

Golden shower, twice removed.

[–] [email protected] 18 points 1 year ago (6 children)

So, I'm no chemist, but if H2O is already oxidized, what do you call it when you make hydrogen peroxide - H2O2?

[–] [email protected] 20 points 1 year ago* (last edited 1 year ago) (1 children)

You call that an unstable compound that doesn’t want to exist. Hydrogen peroxide is constantly looking for an excuse to decompose back into water and oxygen. Making it is like rolling a barrel uphill. As soon as you let go, the barrel will roll back down to the bottom of the valley.

[–] [email protected] 3 points 1 year ago

It’s like rolling a barrel up a bumpy hill.

[–] [email protected] 11 points 1 year ago

The oxygen atom in a water molecule has an oxidation number of -2 (which is as reduced as it can get in common compounds you’re likely to find, and it has no reason to react further). In hydrogen peroxide, the oxygen atoms have an oxidation number of -1, so not quite as reduced as oxygen would rather be (which is why H2O2 is gonna oxidize whatever is around it. Those oxygen atoms are gonna get those sweet, sweet electrons one way or the other by god!)

The hydrogen atoms are identical between H2O and H2O2; that’s not where the magic happens, so to speak.

[–] relative_iterator 8 points 1 year ago

Super oxidized?

[–] [email protected] 6 points 1 year ago

Checkmate, chemists!

[–] [email protected] 5 points 1 year ago

Per - a prefix meaning perfect, thoroughly, or completely.

[–] [email protected] 3 points 1 year ago

DiHydrogen Dioxide?

[–] [email protected] 10 points 1 year ago (1 children)

You just have to wait for it to get hot enough to ~~grill~~ steam the burgers and franks.

[–] [email protected] 7 points 1 year ago (1 children)

Mmm, mouth-watering hamburgers

[–] [email protected] 4 points 1 year ago (1 children)

I thought we were having steamed clams?

[–] [email protected] 6 points 1 year ago (1 children)

Oohhh no I said steamed hams!

[–] [email protected] 5 points 1 year ago

And you call them steamed hams, despite the fact that they are obviously grilled?

[–] [email protected] 9 points 1 year ago

Entropy's a bitch.

[–] [email protected] 8 points 1 year ago (1 children)

Did you try to burn the water while showering?

[–] [email protected] 4 points 1 year ago

Yes, but the fire went out somehow and then I couldn't start it again.

[–] [email protected] 5 points 1 year ago (1 children)

So what would you call it when you combust water by exposing it to burning metals like magnesium?

[–] [email protected] 11 points 1 year ago (1 children)

Honest question. Isn't the metal combusting at that point?

[–] [email protected] 6 points 1 year ago

Both contribute to the combustion, but it's the metal that's fuelling it while water plays the role that air/oxygen usually would. I think codyslab did a video where he had a flame fed by air in an atmosphere of methane which demonstrates the concept that actually you need both fuel and oxidiser for the flame, and one "burns" in an "inert" atmosphere of the other

[–] [email protected] 5 points 1 year ago (1 children)

Reminds me of a joke me and my freinds made about a hipster restaurant that sells "deconstructed water" that's just a balloon filled with hydrogen and a match.

load more comments (1 replies)