What is Chlorine Trifluoride and How Does it React with Fire?

[nomisrosen]

I know that oxygen is necessary for fire to exist, but could there perhaps be another element that the combusting material could bond to? What is so special about oxygen? Couldn't the right conditions create a reaction similar to oxidation, but with a different element?

 

[cjl]

Sure. Fluorine would be an excellent choice. Chlorine trifluoride ( ) is one of the most vigorous oxidizers in existence, and it contains no oxygen.

 

[russ_watters]

What is so special about oxygen is it makes up 20% of the atmosphere.

 

[nomisrosen]

What I meant was more; why can fire only exist in the presence of oxygen? Can't there be a substitute for this? If not, does this mean that fire is a unique property of earth-like planets? (similar atmosphere)

 

[sophiecentaur]

What is so special about oxygen is it makes up 20% of the atmosphere.

Goldilocks strikes again?

 

[coelho]

What I meant was more; why can fire only exist in the presence of oxygen? Can't there be a substitute for this? If not, does this mean that fire is a unique property of earth-like planets? (similar atmosphere)

Fire can (and does) exist without the presence of oxygen. All that is required is a strong oxidizing substance. There are other substances, like flourine or chlorine that can be good substitutes for oxygen.

For example, hydrogen and acetylene are two combustible substances that ignite spontaneously when in contact with chlorine, even without any oxygen, chlorine having the role of the oxygen as the oxidizer.

So, any planet having a strong oxidizer in its atmosphere can have fire on it.

 

[sophiecentaur]

If you spawned a planet with a Nitrogen / Fluorine mixture then the Fluorine is so reactive that it would react with all the other stuff very quickly and you would need some equivalent to plant photosynthesis to regenerate the Fluorine gas from its compounds. But the energy needed for the reaction would be a lot greater so they would have to work by UV, rather than visible light. This would mean a different form of 'life' with a different type of DNA and all the rest of it.

Remember that Oxygen is only in the atmosphere because of life forms. The atmosphere started off as a reducing one and not an oxidising one.

 

[Iron-Stein]

Hmm the answers have been too knobby and impractical.

Oxygen is good for most terrestrial fires... no doubt about that.

But we need to think in terms of electrical valencies and combinations there of; and the Hanson Theorum of "Relative to what?".


To make a bench mark - say WOOD, and AIR - with 20% oxygen.

For all practical purposes that would fit the definitions of FIRE.

Ok FIRE relative to what? What defines fire and under what conditions.

Iron heated to near melting point and then sprayed with a stream of oxygen - is also FIRE.

Iron slowly oxidising at room temperature, in the atmosphere is also fire.

So fire is a chemical reaction.

If you alter the temperature and the pressure, you can have chemical reactions between oxygen and nitrogen, and you can have reactions between nitrogen and other elements or compounds.

You can also have reactions at different pressures, and temperatures between sulphure and iron., and you can also have reactions between hydrogen, hydrocarbons and assorted elements, with or without catalysts, in fuel cells...

There are aerobic and anaerobic reactions.

There are acid and alkali reactions.

There is cellular combustion - or reactions. between assorted chemicals, solely with the organisms intent to skim off the energy within the reaction for self sustainance.

There are reactions that like the wood and air fire, give light and or heat or no light and absorb heat.

The speed of the reactions or the intensity of the reactions is I guess a matter of the amount of substance, the speed that it is consumed and the relative energy states between the highest energy and the most rapid dissipation into entropy.

The hot wood fire with heat, light and fast conversion from solid and gas to mostly gases and some ash., is "a fire", but if we open our imagination to the process being based upon the reactions, and the combinations of those reactions, and the temperatures, pressures and the environments that the reactions take place, then the understanding of the word "fire" expands exponentially, and so the the solutions and applications.

 

[sophiecentaur]

knobby answers?
With respect, the question was not particularly 'high quality' or precise.
The term "fire" is a colloquial one and refers to combustion with Oxygen. If you were after alternative chemical reactions as an energy source then perhaps you should have phrased it that way. But your response seem to suggest that you knew this anyway so waddayawant?

What price a rusting-powered car?

 

[nomisrosen]

Sorry I'm not a physicist or anything. Still in high school actually. I just don't really understand what fire is, and why it needs oxygen and not another element. Thanks for your answers anyhow.

 

[sophiecentaur]

OK
Best not to leap in, on only your second post, with such heavy words!
People here are fairly tolerant but if you want the best out of them it's a good idea to stroke them nicely.

I looked on several places on the net and they all seem to agree that "fire" involves oxygen and a rapid chemical reaction.

 

[cjl]

Iron slowly oxidising at room temperature, in the atmosphere is also fire.

I would dispute that

So fire is a chemical reaction.

Yes, but it's a specific kind of chemical reaction, and most of the ones you give as examples don't really fit the definition of fire. I would say that for a reaction to qualify as fire, it has to be rapid oxidation of a chemical (or multiple chemicals), resulting in the release of heat and light.

 

[cjl]

Sorry I'm not a physicist or anything. Still in high school actually. I just don't really understand what fire is, and why it needs oxygen and not another element. Thanks for your answers anyhow.

As stated above, it doesn't require oxygen. Several elements will work.

 

[sophiecentaur]

As stated above, it doesn't require oxygen. Several elements will work.

I'm pretty sure that 'fire' is a term that is reserved to describe rapid oxidation. Let's face it, the terms was in use way before there was experience of anything else. I do think it is a pity when inventive etymology takes over from Science. Why can't we just call anything else a Chemical Reaction? If you don't then where do you stop?

 

[cjl]

Oh, I agree that it is reserved for rapid oxidation. However, substances can be rapidly oxidized without oxygen (as unfortunate as that terminology is for the understanding of chemistry students everywhere). Fluorine and chlorine will also work.

 

[sophiecentaur]

Woops- that was the non-Chemist talking. By "oxidation" I meant combination with Oxygen - which is what 'everyone' would have meant until not long ago. After all the clue is surely in the "OXY' part of the name. Quite honestly, isn't that what fire is all about?

 

[Borek]

I'm pretty sure that 'fire' is a term that is reserved to describe rapid oxidation.

In atomic absorption spectroscopy (AAS) we often use flame atomizers, feed with nitrous oxide (N₂O)-acetylene mixture which gives a temperature of about 2700 °C. That is definitely a flame and a fire.

This is perhaps not the best example of oxidation with a non-oxygen gas, as nitrous oxide decomposes producing nitrogen and oxygen in better ratio than the atmospheric one (hence higher flame temperature; pure oxygen can't be used as burning velocity is too large). I remember reading about other gas combinations used for getting flame temperatures above 3000 °C, unfortunately I can't find them now.

 

[sophiecentaur]

I defer to your superior knowledge. I'm only talking the language of Joe Public - who is well known for being not-too-well informed.

 

[Iron-Stein]

Heat anything up hot enough and it burns quite nicely with nitrogen...

 

[Delta Kilo]

Does this look like a fire to you? http://en.wikipedia.org/wiki/Proton_rocket
Then check out http://en.wikipedia.org/wiki/Hypergolic_propellant

 

[nsaspook]

We use this stuff for cleaning chambers. http://en.wikipedia.org/wiki/Chlorine_trifluoride

chlorine trifluoride has been reported to burn sand, asbestos, and other highly fire-retardant materials, reacts violently with water-based suppressors, and oxidizes in the absence of atmospheric oxygen, rendering atmosphere-displacement suppressors such as Halon and CO2 ineffective. It ignites glass on prolonged contact.[10]

It is, of course, extremely toxic, but that's the least of the problem. It is hypergolic with every known fuel, and so rapidly hypergolic that no ignition delay has ever been measured. It is also hypergolic with such things as cloth, wood, and test engineers, not to mention asbestos, sand, and water — with which it reacts explosively. It can be kept in some of the ordinary structural metals — steel, copper, aluminium, etc. — because of the formation of a thin film of insoluble metal fluoride which protects the bulk of the metal, just as the invisible coat of oxide on aluminium keeps it from burning up in the atmosphere. If, however, this coat is melted or scrubbed off, and has no chance to reform, the operator is confronted with the problem of coping with a metal-fluorine fire. For dealing with this situation, I have always recommended a good pair of running shoes."