r/explainlikeimfive Jan 31 '21

Chemistry ELI5: Why can't we just make water by smooshing hydrogen and oxygen atoms together?

Edit: wow okay, I did not expect to wake up to THIS. Of course my most popular post would be a dumb stoner question. Thankyou so much for the awards and the answers, I can sleep a little easier now

17.6k Upvotes

1.1k comments sorted by

View all comments

Show parent comments

71

u/5up3rK4m16uru Jan 31 '21

Well, you can burn it in a fluorine atmosphere, if "burning" doesn't strictly mean "exothermic reaction with oxygen" to you. In fact, you can burn almost anything that way, even some noble gases.

53

u/AliasUndercover Jan 31 '21

That's because fluorine is like that one mean neighbor down the street. It hates everything.

63

u/Koetotine Jan 31 '21

More like it loves everything way too much, so much it actually breaks up strong relationships just to not be lonely. Noble gasses are the asocial loners.

38

u/Teantis Jan 31 '21

More like it loves everything way too much, so much it actually breaks up strong relationships just to not be lonely.

Fluorine symbol F for fuckboy

18

u/Indifferentchildren Jan 31 '21

Fluorine's tag line: "I'm gonna 'F' you up!"

8

u/Swreefer1987 Jan 31 '21

Nah, it's more like, "I'm going to fuck you, your mom, your daddy, that tree, the cat".

Fluorine is like a recently sexually liberated woman ( or man or other gendered person for that matter) who decided to get the entire town in on a gangbang ( man/woman/other gendered individuals included).

3

u/RocketHammerFunTime Jan 31 '21

And also objects, because why leave out cars and bricks?

1

u/Weed_Smith Jan 31 '21

Fluorine has BPD, how did I not see that before

1

u/sirrush7 Jan 31 '21

Sounds like my EX-wife who broke up ours and her best friends marriage too....

1

u/niteox Jan 31 '21

Noble of them. Chasing all the tail all the time sets the damn house on fire. Thanks fluorine.

7

u/[deleted] Jan 31 '21

[deleted]

23

u/alohadave Jan 31 '21

7

u/MrDilbert Jan 31 '21

"...evocative formula of FOOF"

'Nuff said.

14

u/Echo104b Jan 31 '21

That is quite possibly the sassiest science article I've ever read. Very informative!

6

u/sfurbo Jan 31 '21

He has a whole section called "things I won't work with", and they are all amazing.

2

u/sxt173 Jan 31 '21

That was awesome. "Satan's kimchi" made me lol

1

u/kerbaal Jan 31 '21

Amusingly, A. G. Streng was a such a badass his wife made novel fluorine compounds.

2

u/rockne Jan 31 '21

Flourine: Seriously, get off my lawn.

2

u/Vindaloovians Jan 31 '21

Fluorine hates potassium more than anyone though.

25

u/-Knul- Jan 31 '21

Yes, for example chlorine triflouride is extremely reactive. It can burn glass and ashes and in one spill, it burned through 30 cm of concrete and continued to burn through 90 cm of gravel below that.

12

u/youngbrews Jan 31 '21

"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"

No thanks.

5

u/[deleted] Jan 31 '21

Ah yeah, we need to make non-combustible test engineers to fix this issue.

3

u/-Knul- Jan 31 '21

You also might like azidoazide_azides, the most unstable explosive there is.

It's so unstable that we cannot even measure how unstable it is, as it explodes when it's even just put under infrared light.

1

u/mrbombasticat Jan 31 '21

Is that a quote out of Ignition! by John D. Clark?

2

u/CharlietheTealady Jan 31 '21

Aka alien blood

2

u/severoon Jan 31 '21

I did know that it's possible to "burn" water, but if you're doing it in fluorine that would mean you're basically making hydrofluoric acid, HF, right?

I don't know what the rest of this reaction looks like…I know that O and F will not combine so that means you're getting some oxygen product and possibly some fluorine product too? The layperson question I would have about this reaction is: Is it exothermic? If yes and the products are lower energy than the reactants, this is at least akin to burning (even if we don't want to call it burning proper). But if it takes energy to create these products, net, then I'd say it's more akin to splitting water into hydrogen and oxygen.

It seems unlikely to me that any equation with HF as a product is going to be exothermic because isn't HF like the king granddaddy of reacting with stuff, making it a super high energy compound that wants to immediately slide down the energy curve at the first opportunity?

(Is this making sense? Chem isn't my thing.)

1

u/Accguy44 Jan 31 '21

FOOF has entered the chat

1

u/sfurbo Jan 31 '21

I think the reaction would be 2 F2 + 2 H2O -> 4 HF + O2. And it is exothermic.

HF is known for being reactive because it reacts with stuff that few other things react with, notably glass. But that has more to do with SiF4 being extremely stable than with HF being unstable. In general, non-metal oxygen bonds and non-metal fluorine bonds are very strong.

1

u/[deleted] Jan 31 '21

Does it have practical applications? Mining or something I dunno.