Phlogiston!
I always thought that fire is “just” plasma, but it’s more complicated: https://en.m.wikipedia.org/wiki/Fire
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.
this was wonderfully written!
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
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? 🤔
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'
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.
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.
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.
Death and Destruction 🌋🏘☠️
Or warmth for the rest of your life 🔥🤗
an experience. molecules experience fire. you are viewing the experience. is everybody in. is everybody innnnnn.
The flames you see are electromagnetic radiation generated from high energy particles
I'll take any excuse to share Feynman talking about fire: https://youtu.be/N1pIYI5JQLE?si=KgrM6zZMofRBQ9CH
It is alive. It is a predator. It wants to eat you!
/s
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.
Something that is really good, amazing, crazy(in a good way).
“That song is straight fire”
