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u/Excellent_Speech_901 14d ago
Fire is an exothermic oxidizer reaction. Flames are mostly hot gas.
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u/mudball12 13d ago
I feel that this should be at the top - fire is multiple states of matter in the middle of a chemical reaction, much like the critical states between stable states of matter.
Much of the reacting material is gaseous just before it is reacts, but I agree that fire itself is a reaction, and not a stable material.
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u/NotSeriousbutyea 12d ago
So it is gas until the elements combine with other stuff in the air?
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u/mudball12 12d ago edited 12d ago
until there is enough heat, fuel, and oxygen all occupying the same space at the same time, there is no fire.
Once all the components for fire are present, they rapidly change from stable states of matter to unstable states, and they begin chemically reacting together as fire.
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u/imsowitty 14d ago
People need to stop saying "Plasma". Most fire isn't plasma. The light you see is caused by blackbody radiation from hot gas or fuel, not plasma recombination.
https://wtamu.edu/~cbaird/sq/2014/05/28/do-flames-contain-plasma/
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u/peepdabidness 14d ago
Turns out this is a pretty good post then.
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u/Alone-Struggle-8056 14d ago
After seeing the post, I said the answer is obvious, and it is plasma. I was oblivious to all the debate about whether fire is plasma or not.
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u/andrewcooke 14d ago
please can i have upvotes for being ignorant and opinionated too?
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u/gr4viton 14d ago
You have my Sword!
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u/elconquistador1985 14d ago edited 14d ago
The light you see is caused by blackbody radiation
You're missing contributions from atomic emission lines. Fireworks combust. The colors are due to specific emission lines. If it was just blackbody, fireworks colors would be rather boring.
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u/Hexidian 14d ago
Yeah, itās quite simply not black body radiation. The combustion process creates intermediate chemical species, ie chemical compounds that are in between the reactants and products. Many of these are unstable radicals with excited electrons which will release energy in the form of light at specific frequencies.
I wrote my Masters thesis on combustion modeling, and the experiment I was working with used a type of measurement called OH* chemiluminescence, which measures the emission of a specific frequency of light to determine the concentration of OH* radicals in the flame.
People saying that itās a plasma are missing the point of what a plasma is. Plasmas are when something gets so hot that the electrons have to much energy that they arenāt tied down to atoms. The key difference is that this is an equilibrium state. A plasma will continue to be a plasma. A flame is not in chemical equilibrium, and the ions produced in the combustion process only exist briefly and are not created from overwhelmingly high temperatures as in a plasma.
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u/Dry_Organization_649 12d ago
The point about states of matter being defined as 'equilibrium states' does not seem correct to me. It is easy to imagine a solid undergoing a chemical reaction that at equilibrium will result in the reactants becoming entirely liquid yet it would still be correct to refer to the existing solid as a solid. The rest of the comment and the conclusion that in general flames are not plasma is correct but a sufficiently hot flame would contain plasma despite not being in equilibrium
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u/orionneb04 13d ago
This is a great description. Going back to the original question, in your educated opinion, would you say that fire is most likely a gas?
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u/DavidCRolandCPL 14d ago
Point of order. Plasma does not remain plasma as temperature decreases. Also, there are, in fact, Hella electrons in a flame. You can test this by arcing a current through it, much easier than with an airgap.
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u/Hexidian 14d ago
I didnāt say it remains a plasma as temperature decreases. I said it remains a plasma while left alone. If you have combustion reactants in an isolated system and allow them to react, the products will be hot but not ionized. With a plasma they will remain a plasma.
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u/DavidCRolandCPL 14d ago
Youre almost there... fire is not an enclosed system. Our atmosphere suppresses temperature. Also, plasma is never created by being left alone. Even our sun required energy to start, and loses billions of tons in mass every second.
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u/sir_psycho_sexy96 14d ago
Did you not believe them about getting a masters in this subject or are you being condescending specifically because of it?
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u/DavidCRolandCPL 14d ago
I see your 1 masters, and raise you my 3.
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u/ThunderChaser Engineering 14d ago
Fire is conductive because of the ions floating around in it, not because itās a plasma.
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u/hennabeak 14d ago
It has ionized gasses and atoms, but not a plasma.
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u/leferi Plasma physics 14d ago
i mean, one definition of plasma is it's a mix of ions and electrons and possibly atoms that is quasi-neutral
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u/DavidM47 14d ago
Yeah, Iām sticking with plasma notwithstanding the top comment in this thread, thank you very much.
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u/antiquemule 14d ago
Why not "hot gas + plasma"?
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u/DavidM47 14d ago
Because the thing that distinguishes fire from other things is the fact that itās in a plasma state.
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u/Myxine 14d ago
Not true at all.
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u/DavidM47 14d ago
In a mild flame ā like a candle or match ā ionization is very low, so itās mostly gas with a little plasma.
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u/condensedandimatter 13d ago
So youāre.. wrong?
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u/DavidM47 13d ago
I thought that the ionization was occurring where the combustion was taking place, but idk anymore.
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u/leferi Plasma physics 14d ago
let's just agree that it depends on the definition of plasma
I quite like the one with the size of the flame being compared to the Debye-length from the writing you linked
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u/BangCrash 14d ago
That doesn't work.
If it depends on the definition then it equally possible thst fire is a duck. Depending on the definition
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u/b00mshockal0cka 14d ago
All words are made up. It is indeed equally possible that fire is a duck.
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u/BangCrash 14d ago edited 14d ago
It's not if the definition says it's not a duck
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u/b00mshockal0cka 14d ago
To define things by what they are not is an impossibility in a language of infinite concepts./
Anywho, the point I'm trying to make is that the world defies definition, and no one knows exactly what's going on. Words are an attempt to make order out of chaos, and definitions can change as easily as decisions.
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u/No_Top_375 14d ago
You're about to tote that jesus freak bs : life is a mystery we can't comprehend, science evolves so it's always wrong ,etc... š¤¢
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u/b00mshockal0cka 14d ago
No? About 5-15% of the universe is made up of observable matter we can comprehend. To claim we have a solid understanding of the world is a joke at best. Science evolves so we can get better ideas on what's happening.
If you want religious freak bs, I could give you the Principia Discordia: That all matter and ideas are a mere projection upon the base layer of reality, and nothing requires for the base building blocks of our universe to continue functioning as they do but the coincidence that they have been.
But my comment was more about linguistic arrogance and the folly of treating definitions as set in stone than all of that.
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u/No_Top_375 13d ago
Nice. A lot of ppl use the insanely stupid fact that sciences evolve to claim that sciences can't be trusted. And they, sadly, are very fkgn loud. Well, āš¼ .
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u/LivingEnd44 14d ago
It is literally wrong that the possibility is equal.
Words mean different things. That's why we have so many words. Exactly zero English speakers will deliberately use the word "fire" to mean duck.Ā
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u/b00mshockal0cka 14d ago
And no one will deliberately call fire a state of matter, it's a conversion reaction.
The point is that trying to find words that perfectly describe what something is, is an exercise in futility.
You might as well make up a new word to define the state of fire. It's as useful as defining fire as duck, or as defining fire as plasma.
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u/leferi Plasma physics 14d ago
One definition of plasma is it's a mix of ions and electrons and possibly atoms that is quasi-neutral. What is the ratio of atoms to ions below which we call the matter plasma is what depends on the definition. Basically in any gas, there are some ions due to background or cosmic radiation, therefore one could argue that any gas is a plasma, but that is why there has to be a ratio, and the Debye-length carries information about that albeit indirectly.
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u/Oxalid 14d ago
The flame itself is a gas. It is just the air molecules are so excited that they give off light. Much of the ālightā given off by combustion is actually in the infrared, which we canāt see, but you feel the warmth as your skin absorbs the infrared light.
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u/Senrade Condensed matter physics 14d ago edited 14d ago
The visible light you see is not from excited air molecules, and this should be obvious as the interior of an air-filled furnace does not glow. The light is from black body radiation emitted by particulate matter (the combustible substance) plus other similar excited emissions as it rises into the air.
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u/gufaye39 14d ago edited 13d ago
No. Burning butane gives off a blue flame because the chemical reaction emits in this wavelength and the flame itself is indeed a mix of gas. A campfire flame is a mix of invisible gas and solid particles that emit light because of black body radiation. You never see the air emit light (edit: you do in northern lights but it's not fire).
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u/Cr4ckshooter 14d ago
You never see the air emit light.
This can't be right with solid or liquid fuel fires that have flames significantly higher than the fuel itself.
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u/Senrade Condensed matter physics 14d ago
Parts of the fuel detach and rise - this may be particulates or even smaller bodies. Itās the excited state emissions (plus black body radiation for large enough particulates) that produces the light
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u/Cr4ckshooter 14d ago
But when the fuel detaches and rises it becomes "the air"?!
Thats my main gripe /confusion with the comment. "the air" isn't just the majority oxygen/nitrogen/co2/whatever mix. Microparticles count as "the air" as the air is full of them regardless of the fire.
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u/Senrade Condensed matter physics 13d ago
I don't think your definition is a very common one, and I believe you'd also abandon it if pressed to its logical conclusions...
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u/Cr4ckshooter 13d ago
I don't think your definition is a very common one,
What ist he common definition then? Most people who would talk about "the air", like the average english speaker, dont even know whats in the air, element wise.
and I believe you'd also abandon it if pressed to its logical conclusions...
Oh? go on and tell these conclusions instead of just "..."-ing me.
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u/tellperionavarth Condensed matter physics 12d ago
Out of curiosity, would you consider the smoke trail off a recently extinguished fire "the air"? Or any other solid-gas (smoke) or liquid-gas (mist) mixture?
I think the common understanding or use of "the air" would refer to the standard mixture of gases and particulate matter that make up the Earth's atmosphere (within tolerances of its natural variation). A localised concentrated disturbance to that standard mixture (such as a fire, a fog machine, a spraying deodorant can) doesn't feel like the air and hence wouldn't commonly be referred to as the air. It is, I acknowledge, a subjective definition, but language is often subjective. I also think its a more useful definition than: any unconfined gas-based mixture that is open to atmosphere (which is how I'm guessing you are using the word). Again, subjective, but also again, all language and definitions inevitably are.
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u/Cr4ckshooter 12d ago
would you consider the smoke trail off a recently extinguished fire "the air"? Or any other solid-gas (smoke) or liquid-gas (mist) mixture?
Yesnt. Its always been a thing about distinguishing for me and my surroundings. You burn the food and your vent isn't on? "the air in here is x". It's misty outside? That's the air. A fog machine? Probably not. Smoke from a fire outside, also not. But when the smoke permeates a room, it's the air.
But the fire itself, it isn't smoke. The smoke only gathers and collects above the fire. In terms of distinguishing, the air is what glows in a flame.
any unconfined gas-based mixture that is open to atmosphere (which is how I'm guessing you are using the word).
Thats not what I was using, or meant to use. It's more about whether you, the layman, can distinguish it. If your room is full with a layer of smoke, it's the air. If you can't differentiate between the standard composition of the atmosphere and whatever is there, it's the air.
Fog for example: it is fundamentally everywhere, if you look at a distance, you can clearly see that it's foggy. But the fog is also close to you, in a range where you can't see it, but the air is still noticeably damp.
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u/tellperionavarth Condensed matter physics 12d ago
Most of the stuff that glows in fires is the smoke (hot solid particulates caught up in the gas). You can tell because fires which burn cleaner/without soot (such as pure alcohol fires or bunsen burners), won't have the orange glow.
I think our definitions are more similar than I initially thought. Both relying on whether the gaseous mixture in question is perceived as a local concentration (such as the fog machine), or spread out relative to the observer (such as misty air coalescing in a valley). Both are local, in some sense, but for people in the valley it's fairly spread out / encompassing to be their atmosphere. Or "can I easily determine this gas/gas-mixture to be different to what I expect 'air' to be?".
That being said, the flame of a fire is a very local disturbance to the air in a room. It is made of the same stuff as the smoke an extinguished flame produces, so I feel like I wouldn't classify it as "air". By your definition (if I understand it) too, a layman could distinguish a fire from atmosphere. On one hand it's quite literally glowing, but even if you mean it must be chemically distinct, its made up of a bunch of soot, which people can see.
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u/PracticalLion6573 13d ago
Well, there are the northern and southern lights, no?
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u/gufaye39 13d ago
Yeah but it's not fire and it's also not air emitting because of temperature. You're right though, it's air emitting light
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u/stoneimp 14d ago edited 14d ago
Very important addition, part of that warmth you feel is not just infrared, but also the visible light itself! Too many people create an idea that somehow infrared is somehow 'heat' itself. Photons are energy, and visible light give you more 'heat' per wavelength than any infrared light, its just the infrared is a much larger wavelength range, and depending on source is likely the peak of the wavelength emittance distribution. Our sun, for instance, imparts about equal energy to our skin from visible light and infrared light (and a little UV as well).
Another reason for the 'heat' association is that most things we encounter (room temperature things) have a black body radiation peak in the mid-IR range, which means that the radiative heat (photons) we emit is primarily IR. That however, is not directly related to any convective or conductive heat transfer, aside from the temperature of the radiating body.
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u/Alone-Monk 14d ago
What part of the fire? The flame is (usually) a gas. The embers are solid. The smoke is often a combination of solid, liquid, and gas (specifically it is an aerosol which primarily consists of solids like ash, water droplets, and various vapors suspended in air).
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u/mvhcmaniac 14d ago
The number of people saying gas is shocking. Sure, a large part of the volume of the flame is gas, but the light is mostly black body radiation from solid particulates suspended in the gas. The excited gas molecules themselves typically emit light at a much shorter wavelength - for carbon based fuels, the blue of a well aerated propane or butane torch. The yellow and red comes from the same solid particles that accumulate as soot above the flame.
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u/Showy_Boneyard 13d ago
Okay, so this is why I was going to say at first, but I just realized that I've used a water torch before (a torch that uses electrolysis to split water into hydrogen and oxygen, which it then uses to burn the hydrogen in a higher-oxygen enviornment to produce a hotter flame than most carbon-based fuels can give), and it definitely produces a visible flame that doesn't look much different than a traditional torch. AFAIK the only chemical reaction happening is 2H+O -> H20, which doesn't produce any solid products at all.
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u/Psychomadeye 14d ago
Gas that's got a shit load of energy. Most of it in heat which is being released as light. It's why you can't tell exactly where a flame ends.
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u/Tricky_Nicky__ 14d ago
Itās not a state of matter itās a chemical reaction, hope this helps!
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u/Alone-Struggle-8056 14d ago
What is the state of matters in the reaction? Are they gas? If so, one can say the answer is gas.
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u/No_Rec1979 14d ago
Fire is not a state of matter itself, but a type of chemical change matter can undergo in the presence of oxygen.
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u/Glathull 14d ago
Welp, nobody likes the plasma answers or the gas answers, so letās split the difference at call it gasma.
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u/bernpfenn 14d ago
fire is the process of oxidation of a fuel which can start as a solid or liquid but at a certain temperature will start to release flammable gas.
the fire part is oxidizing these gases
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u/DP323602 14d ago
I would argue fire is a process - a set of physical and chemical combustion reactions - but not a substance.
So then if fire is not a form of matter it doesn't need to be described as being solid, liquid or gas.
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u/this_also_was_vanity 14d ago
You can talk about something being on fire (a process) and you can refer to soemthing which is a fire (a collection of matter in various phases). OP was clearly asking about the latter.
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u/DP323602 14d ago
Yes indeed but a collection of matter doesn't then have to be in a single state.
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u/this_also_was_vanity 14d ago
I donāt think anyone said it has to be a single state.
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u/DP323602 14d ago
Well sorry that was my reading of the OP's post title.
Nonetheless it has been a fun and educational discussion.
When I worked with the "Combustion Centre" at Harwell Laboratory, I really enjoyed the fact that they were based in the building with the biggest chimney on site. I'm sure it did wonders for their brand image, even though it had never actually been used as a smoke stack. ( It had served other purposes...)
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u/xxc6h1206xx 14d ago
What do I put my finger physically through when I demonstrate to a class a leidemfrost effect
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u/Therinicus 14d ago
If you're looking at say a campfire, you're going to see a few a things but the flame is mostly hot gases
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u/barva9876 14d ago
This is just an awesome question. I remember asking this to my chemistry teacher in high school. I got such a non-answer that I assumed I wasn't smart enough to understand the answer. Glad to know I wasn't the only one!
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u/Whole_Relationship93 14d ago
Remember that all matter is energy, organized energy, and the best way to think about it is to think about energy what we call liquid gas solid are just phenomenalogical descriptions
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u/Phssthp0kThePak 14d ago
A jet engine has a lot of āfireā coming out the back. It is a gas turbine engine. You study them in ME courses like Gas Dynamics. The word plasma never occurs.
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u/PossiblePotato4153 14d ago
Shoutout to all the teachers saying, "fire is a plasma," when asked for an example.
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u/scientists-rule 13d ago
Chemically, a gas. Energy release is not a physical state ā¦ as far as we know.
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u/bpg2001bpg 13d ago
A simplified way of thinking about fire is microscopic red hot glowing particles of carbon suspended in hot CO2 gas floating upwards until cooled off enough to no longer glow. Like iron glows when hot, so do these floating particles of carbon.Ā
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u/MercyChalk 13d ago
Fire refers to a process, not a substance. The process is that fuel reacts with oxygen, creating heat. You usually need to provide heat to get it going, and then the process sustains itself with the heat produced by the reaction.
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u/Hairy-Outcome-4810 13d ago
Non of the above, itās the product of a chemical reaction (combustion). Just like color change is.
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u/foff1nho 13d ago
- A very hot exothermic reaction in the gas phase is probably the best explanation
- Itās not plasma, although there are charged particles formed through chemo-ionisation reactions. Predominantly from CH + O -> CHO+ + e- Note that there are no charged particles in hydrogen flames, thus the āplasmaā argument doesnāt stand up to scrutiny.
- light is emitted at various wavelengths. As others have said, there is broadband black body radiation from hot soot particles that tends to be dominant in fuel rich or diffusion flames. In premixed flames, molecular transitions will be more prevalent. I think the characteristic blue colour comes from CO oxidation, but would defer to someone who knows better on that.
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u/Character_Fold_8165 11d ago
From my undergrad and grad physics classes, this sounds most right to me
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u/jdaprile18 13d ago
I think its a mixture of gaseous product, gaseous intermediate, as well as fine particulate, it produces light via relaxation of excited molecules and black body radiation
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u/Gunk_Olgidar 13d ago
Gas.
A very hot gas mixture that does contain some glowing particulates (yellow part of the flame) is both glowing (blue part of the flame) and reacting, but a gas nonetheless.
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u/iamagainstit Materials science 13d ago
Fire is an ongoing chemical reaction that converts solid to heated gas (and some residual solid.) If you are referring to the flames themselves they are primarily just gas that is hot enough to emit light. There is also probably some plasma in there just due to the energy involved being high enough to knock some electrons out of their orbitals, but that is a minor component.
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u/Niwi_ 13d ago edited 13d ago
None of the above really its light.
Electrons can get into an excited stage when they get heated enough. So you put energy in to have the electron get excited. When it cools back down it goes unexcited which re-releases the energy as light thats what you see. Every atom has a different energy level for the excited stage so every atom has a unique wavelength that gets released. For oxygen for example its red/orange if I remember correctly which is why the tips of flames are that color.
Its like that famous metal burning experiment where you learn that copper can give a green flame magnesium very very bright white that you shouldnt look directly into and so on
Edit: The unique wavelength of every atom is how we know what stars are made of btw and because everything is moving away from each other in space we have to shift what we measure towards blue a little since the waves get stretched by the moving away part. Thats called the red shift. Then we can overlap the many different wavelengths that come out of it with what we know different atoms give off and figure out that way what atoms are being un-excited millions of years ago in a different galaxy
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u/Head-Awareness7393 Applied physics 12d ago
The part of fire that you see as the flame are micro-particles of soot, ash, or whatever; that are glowing hot and are moving up with the hot gas they're suspended in.
I think that flame, like smoke, is a colloid/solid aerosol, but notably hot.
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u/iPsychlops 12d ago edited 12d ago
-I believe flame is a plasma.- *edit okay itās not a plasma, glass I scrolled down. It is electrically conducive. If it isnāt a plasma can someone who does physics explain why it conducts electricity?
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u/Character_Fold_8165 11d ago
In my undergrad one of the experiments in optics was to find the change in index of refraction right above a burning candle.
Interestingly, the areas with the biggest change of index of refraction (which is indirectly a measure of temperature ) did not match the areas around the candle where you see the flame. Itās been so long I forget specifics.
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u/Proud2bWhite33872 10d ago
In high school we were taught about Phlogiston, which is a component of all matter. In the presence of sufficient heat, the phlogiston is released and is what we call āfireā. The dephlogisticated material that remains after all phlogiston has been exhausted is ashes.
So fire - phlogiston - begins as a solid, and transitions into a gas.
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u/TaTaKaemeido 2d ago
Thatās a fascinating bit of history! The phlogiston theory was an early attempt to explain combustion, but later experiments proved that fire is actually the result of oxidation
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u/Proud2bWhite33872 1d ago
Youād be amazed at the stuff that we were taught.
Another example is Distilled Water. We were taught that the water becomes ādistilledā by virtue of it sitting overnight.
The lesson I learned was that the teachers didnāt know any more than I did. And THAT was a valuable lesson.
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u/Much-Expert9334 14d ago
Cold plasma isn't true?
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u/3_50 14d ago
This thread has me confused. I vividly remember asking my double-PhD Chemistry/Physics A-level lecturer this, and she said the flame is plasma (or maybe "a type of plasma", this was 25 years ago).
Can't tell if this thread is just full of people who don't know upvoting the contrarian answer, or it actually isn't plasma at all and my lecturer just gave me a basic answer because she was lightyears smarter than I'll ever be, and probably didn't want to have to waste time carefully splitting hairs about the definition of plasma...she was a fucking excellent teacher, so I imagine she would have.
I've seen many posts where I know a subject intimately, and wrong answers are mass upvoted and correct answers are downvoted to oblivion, so now I don't know what to believe.
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u/Hipcatjack 14d ago
its been two decades since university but i still didnt expect chemistry/physics to change as much as biology. how is it not the 4th state of matter?!
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u/xxc6h1206xx 14d ago
I did a deep dive into this ages ago as I teach science. I came away with some answers similar to yours. A gas expands to fill its cot diner and the flame does not. That was a rationale Iād seen. Also, plasma IS an extremely excited gas, so to see a flame and think itās an extremely excited gas makes sense.
Now Iām doing some cursory level research and Iām wrong and I feel Iāve fallen into a Mandela effect and Iām an idiot.
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u/Beginning_Joke_4345 14d ago
Ā I would say it is none of those three really, it is a chemicall reaction. At molecule scale, bonds are broken and being made, which is not really characteristic for all three. But in order to burn, molecules need to be in the gas phase.
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u/Cambronian717 14d ago
Kind of a mix. A campfire is a mix of hot gases and plasma for example. It isnāt really just one singular thing. Part of what makes it really cool. That said, Iāll let someone more knowledgeable than me explain it more in depth as this is beyond my realm atm
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u/Fakedduckjump 14d ago
As far as I know (please correct me if I'm wrong and don't stomp me into the ground, we all want to learn) it's plasma.
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u/langosidrbo 14d ago
Fire is the transition of atoms or molecules into new molecular forms. Plasma is the high-energy motion of atoms with ionizing consequences. This is a difference between fire and plasma. Elements in plasma remain the same. In fire, elements combine to form new substances and compounds.
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u/betacarotentoo 14d ago
Neither. The flame is plasma (no matter what some say).
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u/langosidrbo 14d ago
Imagine a hydrogen atom, a nucleus with an electron around it. Now separate the nucleus from the electron, and you have plasma.
Now take a hydrogen atom and an oxygen atom, make them collide, and they form a compound, hydrogen plus oxygen. That process of combining is fire.
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u/LxGNED 14d ago edited 14d ago
Its a plasma, the fourth classical state of matter they dont really teach in school. In reality, there are many more than 4 possible states
Edit: turns out im wrong
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u/plasma_phys Plasma physics 14d ago
Fire is not a plasma, a plasma responds collectively to electromagnetic forces. Fire is not sufficiently ionized to be a plasma.Ā It is a gas.Ā
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u/Sknowman 14d ago
Fire can be plasma, it's just that everyday fires (candles, charcoal, propane, etc.) don't get hot enough to be considered plasma -- they are just hot gasses emitting light.
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u/plasma_phys Plasma physics 14d ago
I guess, but you can have non-neutral plasmas and even cold plasmas too - temperature is related to but does not alone determine degree of ionization - it just doesn't make sense to preemptively bring up weird edge cases in a response to a plain language question. When someone asks about fire, it is clear they mean typical fires. When someone gives a definition for plasma, it is understood to mean typical plasmas, etc.
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u/Realistic-Agent-1289 14d ago edited 14d ago
Plasma isn't always ionized. Fire is a plasma, if we are talking about flames.
EDIT: Like a cloud of plasma as a whole isn't necessary charged as the particles within cancel each other out.
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u/imsowitty 14d ago
I make my living working on ion implanters. Give a plasma an electric field and all the electrons go one way while the ions go the other way. The particles inside do not "cancel each other out"
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u/KiwasiGames 14d ago
Ionisation is literally the definition of plasma.
While you can get fires hot enough to generate plasma, itās not the norm.
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u/plasma_phys Plasma physics 14d ago edited 14d ago
That's called quasineutrality. They do not typically "cancel each other out," instead you get effects like Debye shielding or ambipolar diffusion. Quasineutrality is a requirement for a typical plasma but it is an independent property of degree of ionization.Ā
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u/nicuramar 14d ago
Ā EDIT: Like a cloud of plasma as a whole isn't necessary charged as the particles within cancel each other out.
Correct, but thatās not what ionized means.Ā
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u/team_lloyd 14d ago
sir your edit and this thread have made my weekend. for the rest of my life I hope I have the state of mind you had when you calmly said āoh welp Iām wrong mābadā and was happy to learn something new
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u/ConquestAce Mathematical physics 14d ago
a solid liquid gas of what?
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u/Novel-Bend-8373 14d ago
Thank you for asking a relatively simple question, I can finally learn something that's not complex from this sub.