this post was submitted on 29 Nov 2023
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Memes

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A meme is an idea, behavior, or style that spreads by means of imitation from person to person within a culture and often carries symbolic meaning representing a particular phenomenon or theme.

An Internet meme or meme, is a cultural item that is spread via the Internet, often through social media platforms. The name is by the concept of memes proposed by Richard Dawkins in 1972. Internet memes can take various forms, such as images, videos, GIFs, and various other viral sensations.


Laittakaa meemejä tänne.

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[–] [email protected] 42 points 11 months ago (5 children)

Water is just burnt hydrogen, or burnt oxygen. Maybe burnt both. Water is hydrogen and oxygen ashes.

[–] [email protected] 9 points 11 months ago (2 children)

Really? I remember asking someone why the two happily ignite, but together never do, and their explanation was that the molecular bond is too strong it keeps them stable?

I was a teenager at the time though, so just accepted it - is this really accurate?

[–] [email protected] 40 points 11 months ago* (last edited 11 months ago) (3 children)

It's absolutely accurate, you're just missing the fact that H2 and O2 have to oxidize, aka "burn," to create that bond. Literally the easiest way to "create" water is to take a flask of pure hydrogen, a flask of pure oxygen that contains roughly 2.5 times the hydrogen vs oxygen to account for inefficiencies, "pour" those flasks into a container, and light it on fire. The ensuing explosion will convert almost all the hydrogen and most of the oxygen into water. Please stand well back, like behind a reinforced bunker wall if you attempt this.

Forming that bond frees up a single Oxygen atom, splitting the bond it has with its partner and causing a reaction that ends up releasing the excess energy of the Oxygen molecule, and bonding one of the Oxygen atoms to two Hydrogen atoms, the extra Oxygen atom then allows the oxidation process to happen. It also releases a large amount of energy, if you're a Hydrogen or Oxygen atom, or a tiny amount of mostly heat energy if you're a human. (Problem if you're a human is that you aren't capable of causing a single H2+O2+e→O1+H2O+e^x, so you're gonna get a large explosion for even small amounts of a mixture)

This is also true of all other "ash" products created by oxidization of pretty much any fuel from trees to iron. Once you "burn" the compound, it becomes chemically inert for further oxidation, because the atomic bonds of the molecules are about as stable as they can get.

This is why, chemically and physicsally speaking, burning or Oxidizing fuel creates plasma that we call fire. That plasma is the excess energy being expelled as the fuel combines with mostly Oxygen, to form ashes.

Water just happens to be the only type of ash we are familiar with that isn't dry, and instead gets things wet. There may be a few others, but I suspect that most of them are acids or bases that we don't regularly have any contact with.

Edit: source: former US Navy Nuclear Power Program Electronics Technician Instructor. I understand the physics involved, and can easily do the math that the chemistry uses. I don't know shit about biology, so there are probably some biological protein chains that negate literally everything I just said.

Edit 2: Sorry for the first 20 minutes, my comment was reversed with O2 and H2. I literally had to type out the math to remind myself how that reaction works.

[–] [email protected] 6 points 11 months ago

Holy shit, that's insane - thank you!

Still surprised water is ash, and that there's combustion involved... Am n00b :)

[–] [email protected] 5 points 11 months ago* (last edited 11 months ago) (1 children)

roughly 2.5 times the hydrogen vs oxygen to account for inefficiencies

Why 2.5 and not 2? Wouldn't a stoichiometric mix be the most efficient?

[–] [email protected] 2 points 11 months ago

I'm assuming this isn't being done in a perfect environment. Some of the gases won't react/will diffuse enough not to react

[–] [email protected] 4 points 11 months ago (1 children)

Hey man, roughly how much hydrogen would be needed to make 25ml of water?

And secondly. Where can I buy purr hydrogen and pure oxygen?

[–] [email protected] 4 points 11 months ago

You just do electrolysis on the spot

[–] [email protected] 4 points 11 months ago

As others said, hydrogen and oxygen gas in the same container will not create water until energy is put in. Fill a Ballon with a balloon with a 2:1 molar ratio of H2 and O2, then pop the Ballon with a flame, and you will get a cloud of water vapor. Without the fire, popping the balloons with a needle will only release the gases.

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[–] [email protected] 34 points 11 months ago (2 children)

Can also be done with sodium and chlorine! Or any number of covalent bonds

[–] [email protected] 14 points 11 months ago (1 children)
[–] [email protected] 2 points 11 months ago

Here is an alternative Piped link(s):

the process is a little more complicated and technically more dangerous.

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[–] [email protected] 7 points 11 months ago

No, salt is not water, deceiver!

You have the right to drink water and to call for hydrological assistance.

[–] [email protected] 19 points 11 months ago (6 children)

So I know this is just a meme but it's oxygen really the only reason fire can exist? Like don't other things burn on their own with no oxygen present?

[–] [email protected] 25 points 11 months ago (2 children)

There are other chemical reactions that produce heat, but fire is specifically a rapid oxidation. There are other oxidizers though that can result in an oxidation type reaction though, a few are even better than oxygen at it even, like fluorine (which is why pure fluorine is such dangerous stuff)

[–] [email protected] 7 points 11 months ago (1 children)

Chlorine Trifluoride is a better oxidizer than Oxygen itself. Hell, the germans in WW2 tried making self igniting flamethrowers with the stuff. But stopped because it was too nasty to work with.

At that point, they might as well just spray it directly on people. Screw using a fuel to ignite when the trifluoride is enough to set fire to literally anything. Even wet sand can be burnt by it.

[–] [email protected] 8 points 11 months ago (1 children)

Which reminds me of this quote "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, aluminium, etc.-because of the formation of a thin film of insoluble metal fluoride which protects the bulk of the metal, just as the invisible coat of oxide on aluminium 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. "

[–] [email protected] 2 points 11 months ago

Yes, from the book Ignition! by John Clark. Also quoted by Derek Lowe in an entry of his "Things I Won't Work With" articles.

[–] [email protected] 4 points 11 months ago

And why it makes great rocket fuel...

...if you ignore all the other side effects

[–] [email protected] 14 points 11 months ago (1 children)

There can be a release of energy without oxygen, but it will not result in a fire, just an explosion. You can make arguments for things like the sun "burning" in the vacuum of space, but that is fusion, and a far different thing than lighting a match.

[–] [email protected] 9 points 11 months ago (1 children)

Fair and as for the sun I've always seen it as more of just a constant nuclear explosion.

[–] [email protected] 12 points 11 months ago (1 children)

Gravity powered fusion bomb

[–] [email protected] 5 points 11 months ago (2 children)

That never makes sense to me!

It blows my mind, really. My own intuitive understanding of gravity just doesn't extend to that kind of reality (he says with a broken collar bone due to essentially 'too much gravity')

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[–] [email protected] 12 points 11 months ago (1 children)

There are plenty of things that can cause fires that are not oxygen, and don't contain oxygen.

The halogens, Fluorine and Chlorine in particular, are powerful oxidizing agents on their own and can produce flames in the same manner as common flames.

Here's a report on the spectra of flames produced by combustion in a Fluorine atmosphere (PDF warning).

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

Now I need a NileRed video on combustion in a fluorine atmosphere.

(Also, props to your username. I see you, fam.)

[–] [email protected] 9 points 11 months ago (1 children)

Some metals (the ones that require super special fire extinguishers) can keep an exothermic reaction going (magnesium I believe, and sodium I'm pretty sure) but rapid oxidation (rusting) is the most common method of combustion.

Oxygen is so combustible that it's toxic to life, and would have killed life as it was a billion years ago (number from my ass) which produced oxygen as a byproduct of photosynthesis if it weren't for the development of mitochondria.

A few other things (elements) can burn without oxygen, but not many, and they normally need a pretty large activation temperature.

[–] [email protected] 5 points 11 months ago (2 children)

So is it just the definition of "fire" itself? Like only something burning with oxygen is "fire" but if it's another fuel source it's not technically "fire" but we call it fire anyway?

[–] [email protected] 9 points 11 months ago

Burning with oxygen is oxidation, things oxidize when the element oxygen binds with another element, which it's very prone to doing. Oxidation with iron is rust, it just happens much more slowly (but still exothermically) than when biological compound oxidize they release energy more rapidly, rapidly enough to cause other nearby organic bonds to break and expose themselves to sites for more oxidation to take place.

There can be electrical fires, chemical fires, classic fires, and self fueling fires (the kind you were originally asking about). There are probably more categories now. Always be sure to use the proper fire extinguisher for the fire at hand.

[–] [email protected] 6 points 11 months ago* (last edited 11 months ago)

I can't find anything that says it's not considered fire if it's not burning with oxygen, just that a fuel needs to be oxidizing and combusting, and the definition of oxidation has expanded so it doesn't necessarily require actual oxygen anymore (even though that's how the word originated).

Here's a neat clip I found of hydrogen-chlorine fire.

[–] [email protected] 3 points 11 months ago

There are very few things that burn without oxygen and are not self oxygenating

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[–] [email protected] 18 points 11 months ago (2 children)
[–] [email protected] 4 points 11 months ago (1 children)

It's also enhances the fire because it is a stronger oxidizing agent. Fluorine is also another strong oxidizing agent and will enhance fires dramatically

Note: Each element or chemical behaves differently with other chemicals.

[–] [email protected] 2 points 11 months ago

Note: Each element or chemical behaves differently with other chemicals.

Can you prove that? 😉

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[–] [email protected] 6 points 11 months ago* (last edited 11 months ago) (5 children)

I mean there is some stuff that makes water flammabe. What was it again? Pretty nasty stuff, that explodes if it touches anything. It's an acid i think?

[–] [email protected] 4 points 11 months ago (1 children)

Fluorine? Or maybe chlorine trifluoride?

[–] [email protected] 2 points 11 months ago (1 children)

Maybe Trichloro silane? I think it was something with "tri", reactive with almost anything and creates a poisonous gas then.

Probably one of them, i give up.

[–] [email protected] 3 points 11 months ago (1 children)

I think it is chlorine trifluoride, which I only know about because of Sand Won't Save You This Time

[–] [email protected] 2 points 11 months ago

Ah yes, this was it. Thanks!

[–] [email protected] 4 points 11 months ago* (last edited 11 months ago) (1 children)
[–] [email protected] 2 points 11 months ago

Nope, but good one too.

[–] [email protected] 3 points 11 months ago

Well technically all of the alkaline metals have pretty strong reactions when in water though to different degrees. So maybe one of them?

[–] [email protected] 3 points 11 months ago (1 children)

Any alkali metal? That's not the water exploding, that's the metal exploding

[–] [email protected] 1 points 11 months ago (1 children)
[–] [email protected] 1 points 11 months ago (1 children)
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[–] [email protected] 2 points 11 months ago

Not an acid, but maybe francium?

[–] [email protected] 2 points 11 months ago

Combustible compounds react with oxygen to form lower energy oxidized compounds. Carbon is oxidized to carbon dioxide. A fully oxidized compound can't be further oxidized under normal conditions.

Water is the most oxidized form of hydrogen. It can't be further oxidized under normal conditions, hence why it's not combustible.

Methane is the most reduced for of carbon, so it really wants to be oxidized. Carbon monoxide is only partially oxidized, so it's still flammable.

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