this post was submitted on 07 Feb 2025
72 points (91.9% liked)

No Stupid Questions

36919 readers
1356 users here now

No such thing. Ask away!

!nostupidquestions is a community dedicated to being helpful and answering each others' questions on various topics.

The rules for posting and commenting, besides the rules defined here for lemmy.world, are as follows:

Rules (interactive)


Rule 1- All posts must be legitimate questions. All post titles must include a question.

All posts must be legitimate questions, and all post titles must include a question. Questions that are joke or trolling questions, memes, song lyrics as title, etc. are not allowed here. See Rule 6 for all exceptions.



Rule 2- Your question subject cannot be illegal or NSFW material.

Your question subject cannot be illegal or NSFW material. You will be warned first, banned second.



Rule 3- Do not seek mental, medical and professional help here.

Do not seek mental, medical and professional help here. Breaking this rule will not get you or your post removed, but it will put you at risk, and possibly in danger.



Rule 4- No self promotion or upvote-farming of any kind.

That's it.



Rule 5- No baiting or sealioning or promoting an agenda.

Questions which, instead of being of an innocuous nature, are specifically intended (based on reports and in the opinion of our crack moderation team) to bait users into ideological wars on charged political topics will be removed and the authors warned - or banned - depending on severity.



Rule 6- Regarding META posts and joke questions.

Provided it is about the community itself, you may post non-question posts using the [META] tag on your post title.

On fridays, you are allowed to post meme and troll questions, on the condition that it's in text format only, and conforms with our other rules. These posts MUST include the [NSQ Friday] tag in their title.

If you post a serious question on friday and are looking only for legitimate answers, then please include the [Serious] tag on your post. Irrelevant replies will then be removed by moderators.



Rule 7- You can't intentionally annoy, mock, or harass other members.

If you intentionally annoy, mock, harass, or discriminate against any individual member, you will be removed.

Likewise, if you are a member, sympathiser or a resemblant of a movement that is known to largely hate, mock, discriminate against, and/or want to take lives of a group of people, and you were provably vocal about your hate, then you will be banned on sight.



Rule 8- All comments should try to stay relevant to their parent content.



Rule 9- Reposts from other platforms are not allowed.

Let everyone have their own content.



Rule 10- Majority of bots aren't allowed to participate here.



Credits

Our breathtaking icon was bestowed upon us by @Cevilia!

The greatest banner of all time: by @TheOneWithTheHair!

founded 2 years ago
MODERATORS
 

Is it gas? What material is fire? Why does fire exist?

top 23 comments
sorted by: hot top controversial new old
[–] TheBananaKing@lemmy.world 78 points 6 hours ago (4 children)

Individual oxygen atoms are very very grabby; they're stage-5 clingers on PCP. They're straight-up homewreckers, and they cannot and fucking will not be alone. They need a friend or two, and they will go and rip molecules apart to take them because fuck you.

Now, if there's nothing else available, they'll pair up with another oxygen atom, and form O2, what people normally call oxygen; the stuff you find in the air.

But it's an uneasy alliance, and the bond angles are all wrong so it's kind of spring-loaded.

And the same goes for lots of other molecules - carbon-carbon or carbon-hydrogen bonds ferinstance are also kind of tense and uncomfortable; it takes a surprising amount of energy to snap them into place, like building a tower of interlocking mousetraps.

So smack an O2 at reasonably high speed (or in other words, at a high temperature) at big structure of carbons and hydrogens, and it's fucking chaos.

The oxygen-oxygen bond splits, and the two halves grab the other atoms, ripping the structure apart and releasing all the energy that went into spring-loading those bonds.

The main byproducts are CO2 (a carbon with two oxygens) and H2O (an oxygen with two hydrogens), both of which are very low-energy, strong bonds.

They're both gases, and all that energy leftover is released as heat, which does two things:

  • raise the temperature enough to do the same thing with even more O2s, causing a chain reaction
  • heat up the released gases (and any bits of random gunk that break off with them) so much that they glow red hot, just like hot iron.

So you get plumes of glowing hot gas-and-particles streaming off the stuff that's burning - and hot air rises, so the plumes point upwards.

But they also cool down quickly in the air, below the glowing-hot point, and that's why flame has a shape: the boundary is how far as they get while still hot enough to glow.

Of course, hydrocarbons and carbohydrates aren't the only things that burn, there's lots of other molecules you can do this to, and the same principle applies. It's just that carbony things tend to burn easily and well, and we're surrounded by the stuff because that's what living things are made of, so that's what you tend to see being on fire the most.

[–] kSPvhmTOlwvMd7Y7E@lemmy.world 5 points 52 minutes ago

I am waiting for the sequel of this story

[–] johsny@lemmy.world 3 points 1 hour ago
[–] truxnell@infosec.pub 10 points 2 hours ago

I could go more science written like this

[–] janus2@lemmy.zip 4 points 4 hours ago

this was wonderfully written!

[–] 5oap10116@lemmy.world 5 points 4 hours ago (1 children)
[–] Kusimulkku@lemm.ee 1 points 26 minutes ago

I can't believe the woke mob canceled phlogiston and luminiferous aether. Smdh

[–] truthfultemporarily@feddit.org 82 points 9 hours ago* (last edited 9 hours ago)

It's a gas where the chemical reaction of the combustion has produced enough energy to heat it up to a temperature where it emits visible light. Kind of like a glowing piece of metal, but in gas form.

It's a mixture of black body radiation and individual spectral lines.

The spectral lines happen when electrons fall from a high to a low energy state and the energy difference is emitted as light.

Black body radiation describes the fact that everything constantly emits electromagnetic radiation (=light). But what kind of light depends on the temperature with colder bodies like us humans emitting infrared whereas warmer bodies like the sun emit visible light. That is also why light temperature is a thing and the unit is Kelvin.

Here are some graphs and stuff: https://physics.stackexchange.com/questions/648273/does-fire-emit-black-body-radiation

[–] DirigibleProtein@aussie.zone 1 points 3 hours ago

I always thought that fire is “just” plasma, but it’s more complicated: https://en.m.wikipedia.org/wiki/Fire

[–] timroerstroem@feddit.dk 24 points 9 hours ago

What the vast majority of people would probably think of when they hear the word 'fire' is actually flames; flames are quite simply particles emitting light.

For an everyday example, take a campfire: The wood logs you see burning are at such a high temperature that they give off methanol (and other flammable chemicals), which is most of what's burning. Apart from the methanol being driven off of the wood, there will be other chemical compounds and/or larger clumps of more-or-less-burned wood that will be carried off. These larger clumps in particular, while very small, are nonetheless large and hot enough to start emitting light in the visual spectrum. This is essentially what a flame is: Particles emitting light.

Fire in and of itself is quite simply rapid oxidation in the presence of oxygen.

The above is, arguably, a gross oversimplification.

TLDR: Flames are particles, fire is combustion.

[–] Darkassassin07@lemmy.ca 16 points 9 hours ago* (last edited 9 hours ago)

https://en.m.wikipedia.org/wiki/Fire

In short: a chemical reaction. You mainly experience the light/heat, but those are just products of said reaction.

[–] Kolanaki@pawb.social 3 points 6 hours ago* (last edited 6 hours ago) (2 children)

I heard it was plasma once, but I don't know if that's true. Plasma is state of matter (like solid, has, liquid). Is burning a state of matter? 🤔

[–] reptar@lemmy.world 1 points 3 hours ago

Usually there's a significant amount of ions in a flame, enough to make a little conductive. That's where the plasma characterization comes from

[–] dnick@sh.itjust.works 2 points 5 hours ago

No, is just a reaction from two molecules into two other molecules. Oversimplification, but you know how vinegar and baking soda react when the come together all fuzzy and bubble? It's the same when oxygen and hydrocarbons meet, except that it take heat to get it going, and conveniently releases more heat, which is usually enough to cause more reaction, often until it runs out of either oxygen or the hydrocarbon.

It would be an even better parallel if vinegar and baking soda didn't react if they were both below a certain temperature, and if the bubbling created heat, which warmed up the stuff next to it. If that were the case you could see a cool thing where you could keep them could, and just touch one spot to start them reacting, and it would spread like 'fire'

[–] Wwwbdd@lemmy.world 2 points 6 hours ago (1 children)

I'll take any excuse to share Feynman talking about fire: https://youtu.be/N1pIYI5JQLE

[–] Mbourgon@lemmy.world 1 points 1 hour ago

That’s incredible. I hadn’t seen that particular bit by him before. Very cool!

[–] humanspiral@lemmy.ca 2 points 6 hours ago

Fire is not an element in itself (ie not a molecule/atom in gas/liquid form). Combustion requires an oxidant like Oxygen or Chlorine and it is a reaction that breaks down other molecules into combinations with the oxydant. Making steam if donor molecule contains Hydrogen, and CO2 if donor molecule contains carbon.

[–] ThePowerOfGeek@lemmy.world 7 points 9 hours ago

Fire isn't a material. It's the effect of a change in state of other materials. It exists in the same way that freezing or photosynthesis exists.

[–] shoulderoforion@fedia.io 3 points 7 hours ago

an experience. molecules experience fire. you are viewing the experience. is everybody in. is everybody innnnnn.

Death and Destruction 🌋🏘☠️

Or warmth for the rest of your life 🔥🤗

[–] Fleur_@hilariouschaos.com 1 points 6 hours ago

The flames you see are electromagnetic radiation generated from high energy particles

[–] TachyonTele@lemm.ee 2 points 8 hours ago

Something that is really good, amazing, crazy(in a good way).

“That song is straight fire”

[–] NeoNachtwaechter@lemmy.world 0 points 5 hours ago

It is alive. It is a predator. It wants to eat you!

/s