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Author Topic: What State of matter is Fire?  (Read 31228 times)

Astronomer_FB

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What State of matter is Fire?
« on: 04/03/2009 00:59:59 »
What is fire's state of matter my teacher tells me gas.  What is its atomic structure and if it is a  gas why does it not expand its volume within its own container like other gases? 

Supercryptid

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What State of matter is Fire?
« Reply #1 on: 04/03/2009 04:17:42 »
It is a gas. The structure of a flame will vary depending on which part of the flame you are looking at. At the very base of the flame, oxygen molecules and vaporized fuel molecules will exist in an unburned state. As you go higher, the fuel and oxygen molecules will be dissociated and will begin to react with one-another. At this point, combustion is incomplete. Higher up, combustion is completed and waste gases are produced (such as water vapor and carbon dioxide). The light and heat generated by the flame are caused by the reaction energy of combustion. You can also tell which parts of a flame are hottest by their color. The blue portion of a flame is the hottest, whereas red will be coolest.

Technically, a flame does expand like a gas. You usually cannot see this. This is because as a gas expands, it gets cooler. When it cools enough, it will no longer produce visible light and it will be invisible. Thus, you can only see the parts of the flame that are hot enough to produce light.

Some people will say that fire is a plasma (and in some cases it is). However, I don't consider plasma to be a true state of matter. It is simply a variant on other states of matter. You can think of, for example, metals to be a form of solid plasma because of the electron "soup" and atomic "kernels" they are composed of. Essentially, they are ionized but have a net charge of zero.

You could have fire with plasma in it by burning metal such as magnesium, since the metal atoms are technically ionized. However, a substance does not need to be hot in order to be considered a plasma. As long as it's ionized, it'll do.
« Last Edit: 04/03/2009 04:19:37 by Supercryptid »

Damo the Optics Monkey

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What State of matter is Fire?
« Reply #2 on: 04/03/2009 07:53:09 »
Also, fire contains solid particulate carbon - hot soot is yellow-orange (cold soot is achromatic- black/white) - sort of like a solid in suspension in the gas that Supercryptid describes.

Astronomer_FB

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What State of matter is Fire?
« Reply #3 on: 04/03/2009 11:20:40 »
Ok thanks but is it possible to actually freeze fire or to have it in a complete liquid or complete solid state? 

lightarrow

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What State of matter is Fire?
« Reply #4 on: 04/03/2009 12:29:50 »
Ok thanks but is it possible to actually freeze fire or to have it in a complete liquid or complete solid state? 
Then it wouldn't be fire anylonger.

Bored chemist

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What State of matter is Fire?
« Reply #5 on: 04/03/2009 18:55:36 »
Fire isn't a thing, it's a process. As such it doesn't need to fit into any of the categories.

lightarrow

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What State of matter is Fire?
« Reply #6 on: 04/03/2009 19:02:18 »
Yes, it should have better talked about "flame".

Astronomer_FB

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What State of matter is Fire?
« Reply #7 on: 04/03/2009 19:53:07 »
Yes, it should have better talked about "flame".
Well can you explain the difference of fire and flame then.

lightarrow

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What State of matter is Fire?
« Reply #8 on: 05/03/2009 08:12:21 »
Yes, it should have better talked about "flame".
Well can you explain the difference of fire and flame then.
As Bored chemist wrote, fire is a process: the process of combustion; so it's not (properly speaking) a physical object as a flame.
« Last Edit: 08/04/2009 14:58:44 by lightarrow »

ScientificBoysClub

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What State of matter is Fire?
« Reply #9 on: 05/03/2009 08:27:47 »
There are four states of matter

-solid
-liquid
-gas
-PLASMA and Fire belongs to plasma !!

Damo the Optics Monkey

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What State of matter is Fire?
« Reply #10 on: 05/03/2009 09:14:16 »
isn't the Bose-Einstain Condensate a state of matter?

BoredChemist is right - fire is a process.

here is a great resource

Astronomer_FB

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What State of matter is Fire?
« Reply #11 on: 05/03/2009 11:04:05 »
isn't the Bose-Einstain Condensate a state of matter?

BoredChemist is right - fire is a process.

here is a great resource
Got it guys thanks alot.

Damo the Optics Monkey

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What State of matter is Fire?
« Reply #12 on: 05/03/2009 11:10:57 »
you are most welcome

Madidus_Scientia

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What State of matter is Fire?
« Reply #13 on: 05/03/2009 17:56:17 »
There are four states of matter

-solid
-liquid
-gas
-PLASMA and Fire belongs to plasma !!


No, it is a hot gas.

Bored chemist

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What State of matter is Fire?
« Reply #14 on: 05/03/2009 18:59:35 »
A flame is composed of plasma- they conduct electricity reasonaby well.

Fuzimatt

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What State of matter is Fire?
« Reply #15 on: 06/03/2009 04:44:30 »
I agree with everyone saying its a plasma. Thats why it has color and conducts electricity.

ScientificBoysClub

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What State of matter is Fire?
« Reply #16 on: 08/04/2009 11:07:57 »
There are four states of matter

-solid
-liquid
-gas
-PLASMA and Fire belongs to plasma !!


No, it is a hot gas.
who said that fire is a gas ?

Chemistry4me

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What State of matter is Fire?
« Reply #17 on: 08/04/2009 11:19:19 »
Madidus_Scientia did. :)

Don_1

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What State of matter is Fire?
« Reply #18 on: 08/04/2009 12:19:13 »
  What State of matter is Fire?


Rapid change???

ScientificBoysClub

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What State of matter is Fire?
« Reply #19 on: 08/04/2009 12:20:25 »
  What State of matter is Fire?


Rapid change???
change...but There are four states of matter

-solid
-liquid
-gas
-PLASMA and Fire belongs to plasma !!
 ....

lightarrow

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What State of matter is Fire?
« Reply #20 on: 08/04/2009 15:00:37 »

 change...but There are four states of matter

-solid
-liquid
-gas
-PLASMA and Fire belongs to plasma !!
 ....

Raghavendra

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What State of matter is Fire?
« Reply #21 on: 12/04/2009 07:45:59 »
I said in earth ......without oxygen

Chemistry4me

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What State of matter is Fire?
« Reply #22 on: 12/04/2009 07:48:13 »
In Earth or on Earth?

Raghavendra

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What State of matter is Fire?
« Reply #23 on: 12/04/2009 07:50:13 »
In the earth,...

Chemistry4me

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What State of matter is Fire?
« Reply #24 on: 12/04/2009 07:52:11 »
Blah, I'm too old for this. :P

 

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