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Author Topic: What is the composition of fire?  (Read 17194 times)

Guillermo Davies

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What is the composition of fire?
« on: 27/07/2008 16:06:07 »
Guillermo Davies asked the Naked Scientists:

Is fire any kind of matter?  If so, which state of matter is it in, plasma,
gas?

What do you think?


 

lyner

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What is the composition of fire?
« Reply #1 on: 27/07/2008 17:47:37 »
Fire is more of a 'process' than a substance, I should say.
The 'matter' in a fire is the fuel and the Oxygen (plus Nitrogen, etc, which play no real part).
The oxidation process is very rapid (and exothermal) which raises the temperature and  provides the activation energy to continue the process.
A plasma consists of a mixture of ions which are separated by virtue of the average thermal energy (i.e. temperature) being greater than the potential energy of attraction between the ions. There may be some flames where this happens but I don't think the temperature is high enough in 'yer average' candle flame.
Aren't the fuels and the oxides covalent compounds so the energy would only be available if they actually combined?
Go on, BC - put me right. I promise not to get abusive!
 

Offline thedoc

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What is the composition of fire?
« Reply #2 on: 30/07/2008 10:17:35 »
Listen to the answer to this question on our podcast by clicking here
 

Offline Bored chemist

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What is the composition of fire?
« Reply #3 on: 30/07/2008 19:12:48 »
Technically a plasma is any ionised gas (subject to being shouted at by physicists) so a candle flame is a dilute plasma. A decent meter will let you demonstrate that a candle flame conducts electricity. Not many of the molecules get ionised, but some do.

Anyway, describing fire as a process rather than a material sums it up rather well.
 

lyner

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What is the composition of fire?
« Reply #4 on: 31/07/2008 17:45:14 »
Why do you hate me so?
You are always putting me right (gnaws knuckles and kicks the cat).


I should have remembered the 'flame probe' for detecting high voltage potentials.
« Last Edit: 31/07/2008 17:47:49 by sophiecentaur »
 

Offline Bored chemist

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What is the composition of fire?
« Reply #5 on: 31/07/2008 18:52:36 »
Of course, I love you dearly. But my love of scientific truth tends to win out.
 

Offline lightarrow

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What is the composition of fire?
« Reply #6 on: 01/08/2008 13:09:49 »
Why do you hate me so?
You are always putting me right (gnaws knuckles and kicks the cat).


I should have remembered the 'flame probe' for detecting high voltage potentials.
[I'm one of them who don't hate you, since I didn't even mention the fact that the "matter" in the flame is more the reaction products, than the reagents...  :)]
 

lyner

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What is the composition of fire?
« Reply #7 on: 01/08/2008 14:08:06 »
That's true - particularly around the outside.
 

Pramod Kandel

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« Reply #8 on: 31/01/2010 18:46:42 »
Why are you fighting? Someone tell what actually is fire. Does it have mass? Can it be made to occupy fixed shape? Why does it flutter? Why is it pointed at top? If it is a reaction, what are the reactants and products? If it were a process, I believe it shouldn't have been such a physical thing which could be seen. If it is a matter, it should be within three states. And Mr. Plasma, I request you to clear your concept as Mr. Process did.
 

Anthony Williams \"Bocetti\"

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« Reply #9 on: 05/03/2010 23:41:25 »
Fire is the physical manifestation of an incorporeal reality or the spirit of Yahweh. That is the reason it can't be defined under matter as the other elements are and there has to be three (3) conditions in order to invoke fire. This is showing that the creator Yahweh is a 3-fold unity being the Father, The Word and Holy Spirit. At no point in time will you get Yahweh without the 3-fold unity just like there can't be fire without those 3 conditions present which are the fuel, oxygen and heat.
 

Offline Dr. Junix

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What is the composition of fire?
« Reply #10 on: 29/06/2011 10:01:41 »
Fire is the physical manifestation of an incorporeal reality or the spirit of Yahweh. That is the reason it can't be defined under matter as the other elements are and there has to be three (3) conditions in order to invoke fire. This is showing that the creator Yahweh is a 3-fold unity being the Father, The Word and Holy Spirit. At no point in time will you get Yahweh without the 3-fold unity just like there can't be fire without those 3 conditions present which are the fuel, oxygen and heat.

Amen to that.. So fire proves there is indeed God, and therefore disproves other theories such as the big bang, the evolution and so on.
 

Offline Mr. Data

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What is the composition of fire?
« Reply #11 on: 29/06/2011 10:09:50 »
playnext=1&list=PL512787F5D8869660
 

Offline CliffordK

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What is the composition of fire?
« Reply #12 on: 29/06/2011 10:40:02 »
Fire is the physical manifestation of an incorporeal reality or the spirit of Yahweh. That is the reason it can't be defined under matter as the other elements are and there has to be three (3) conditions in order to invoke fire. This is showing that the creator Yahweh is a 3-fold unity being the Father, The Word and Holy Spirit. At no point in time will you get Yahweh without the 3-fold unity just like there can't be fire without those 3 conditions present which are the fuel, oxygen and heat.
Amen to that.. So fire proves there is indeed God, and therefore disproves other theories such as the big bang, the evolution and so on.

I am not sure you could conclude that fire proves God.

However, if you think of Traditional Chinese Balance (Medicine?), there are five basic elements:

Fire, Wood, Earth, Water, and Metal.

http://healthy-ojas.com/systems/tcm-five-elements.html

I can't really say much about the theory, but:
Quote
Fire is characterized as draught, heat, flaring, ascendance, movement, etc.
 

Offline imatfaal

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What is the composition of fire?
« Reply #13 on: 29/06/2011 11:19:13 »
Let's keep it Science please guys! 
 

Offline Mr. Data

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What is the composition of fire?
« Reply #14 on: 29/06/2011 11:20:22 »
Fire is the physical manifestation of an incorporeal reality or the spirit of Yahweh. That is the reason it can't be defined under matter as the other elements are and there has to be three (3) conditions in order to invoke fire. This is showing that the creator Yahweh is a 3-fold unity being the Father, The Word and Holy Spirit. At no point in time will you get Yahweh without the 3-fold unity just like there can't be fire without those 3 conditions present which are the fuel, oxygen and heat.
Amen to that.. So fire proves there is indeed God, and therefore disproves other theories such as the big bang, the evolution and so on.

I am not sure you could conclude that fire proves God.

However, if you think of Traditional Chinese Balance (Medicine?), there are five basic elements:

Fire, Wood, Earth, Water, and Metal.

http://healthy-ojas.com/systems/tcm-five-elements.html

I can't really say much about the theory, but:
Quote
Fire is characterized as draught, heat, flaring, ascendance, movement, etc.

Yes... the link I gave gives a very accurate description of such myths.
 

Offline Mr. Data

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What is the composition of fire?
« Reply #15 on: 29/06/2011 11:21:18 »
Let's keep it Science please guys! 

Fire is just infrared light.
 

Offline imatfaal

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What is the composition of fire?
« Reply #16 on: 29/06/2011 12:19:36 »
Let's keep it Science please guys! 

Fire is just infrared light.

No. fire is a process in which combustible materials form a hot gas/weakly ionised plasma
 

Offline Mr. Data

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What is the composition of fire?
« Reply #17 on: 29/06/2011 12:29:47 »
Let's keep it Science please guys! 

Fire is just infrared light.

No. fire is a process in which combustible materials form a hot gas/weakly ionised plasma

what do you think this combustable material emmits? wiki states:

''Fire is the rapid oxidation of a material in the chemical process of combustion, releasing heat, light, and various reaction products''

Now ask what infrared light is.

''We experience infrared light every time we feel the heat of the sun on our skin or the warmth of a camp fire.''

http://astro.uchicago.edu/cara/about_cara/defn/irlight.html

I know my data.
 

Offline imatfaal

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What is the composition of fire?
« Reply #18 on: 29/06/2011 13:49:35 »
Sorry - it's fairly simple; Fire is not just infrared light. (fire gives off infrared amongst other things). You might want to google convection, conduction and radiation as heat transfer methods.  On the campfire example - this is one of the reasons it is much hotter downwind of a campfire than upwind.
 

Offline Mr. Data

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What is the composition of fire?
« Reply #19 on: 29/06/2011 14:10:39 »
You:

''Sorry - it's fairly simple; Fire is not just infrared light.''

Me: pre:

''fire is just infrared light''

You:

''No. fire is a process in which combustible materials form a hot gas/weakly ionised plasma.''

Make up your mind please.
 

Offline CZARCAR

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What is the composition of fire?
« Reply #20 on: 29/06/2011 14:27:14 »
ch4 + o2= co2 + h2o. @ the = sign the flame exists. Is there a difference in the mass on the left side [ch4+o2] of the = sign from the right side [co2+h2o]?  ASSUME THE EQUATION IS PROPERLY BALANCED,sorry.
 

Offline Mr. Data

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What is the composition of fire?
« Reply #21 on: 29/06/2011 14:31:47 »
ch4 + o2= co2 + h2o. @ the = sign the flame exists. Is there a difference in the mass on the left side [ch4+o2] of the = sign from the right side [co2+h2o]?  ASSUME THE EQUATION IS PROPERLY BALANCED,sorry.

Yes... combustion. If my chemistry suits me well, ch4 is the greenhouse gas... a temperature effect on objects, o2 is the oxygen. As you will notice, these are not fundamental effects. They are atomic. If you want to know the fundamental effects, you ask what fire is made of, and in it's most simplest terms, it is an infrared light, as I have explained. And proved.
 

Offline Mr. Data

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What is the composition of fire?
« Reply #22 on: 29/06/2011 14:34:26 »
In fact, o2 is a molecular construction is it not? We need the fundamental answer, which I have given. Atomic was not even close, and molecular physics is even further from the fundamental answer.
 

Offline damocles

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What is the composition of fire?
« Reply #23 on: 29/06/2011 16:39:08 »
The most familiar form of fire -- orange, yellow, or white flame -- is due to orange, yellow, or white hot sooty particles. It is a solid aerosol, and not really a gas or a plasma.

Blue flame is due to emission of light from several types of diatomic molecule that are formed in the combustion reaction in excited states -- things like C2, CN, CH, and OH. It involves high energy and unfamiliar molecules, but usually not ions as such.

The presence of trace quantities of metals which easily form ions often leads to characteristic colours of flame: potassium gives lilac flame, barium or copper give green, lithium, calcium or strontium give red. But the one that usually dominates is sodium, which seems to get everywhere, and produces a slightly orange yellow colour in a flame -- the same colour as sodium street lights.

You can tell the difference between these different types of flame very easily with a simple pocket spectroscope. Solid aerosols will show a continuous spectrum; typical flame diatomics a banded spectrum, and metal ions will produce sharp spectral lines.
 

Offline Mr. Data

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What is the composition of fire?
« Reply #24 on: 29/06/2011 16:47:51 »
The most familiar form of fire -- orange, yellow, or white flame -- is due to orange, yellow, or white hot sooty particles. It is a solid aerosol, and not really a gas or a plasma.

Blue flame is due to emission of light from several types of diatomic molecule that are formed in the combustion reaction in excited states -- things like C2, CN, CH, and OH. It involves high energy and unfamiliar molecules, but usually not ions as such.

The presence of trace quantities of metals which easily form ions often leads to characteristic colours of flame: potassium gives lilac flame, barium or copper give green, lithium, calcium or strontium give red. But the one that usually dominates is sodium, which seems to get everywhere, and produces a slightly orange yellow colour in a flame -- the same colour as sodium street lights.

You can tell the difference between these different types of flame very easily with a simple pocket spectroscope. Solid aerosols will show a continuous spectrum; typical flame diatomics a banded spectrum, and metal ions will produce sharp spectral lines.

Gas... plasma... still an infrared energy... I don't understand if you are either challenging the debate, or giving your penny in?
 

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What is the composition of fire?
« Reply #24 on: 29/06/2011 16:47:51 »

 

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