Why does fire need oxygen, what's wrong with other fuels?

Question

If fire burns oxygen and paper as fuel, why does the oxygen even need to exist?
What makes oxygen "so important" that it can't be replaced with gasoline, paper, or any other alternative?

EX: If a match was lit in a very small room, the oxygen would quickly be used up. Adding gasoline vapors to the room to compensate for the lost oxygen would NOT keep the fire alive.
WHY!?!?!????

**Please don't give a stupid answer to this.... if you don't know, don't answer**

Answer 1

Fire is a chemical reaction that requires fuel (something that burns) and oxidizer (something that the burning stuff combines with). Fuel by itself cannot burn, it needs something to react with, and that something is oxygen. The fuel (usually a carbon and hydrogen compound) will have its constituent atoms give up their electrons to oxygen which will gladly take them away (most of the time, actually, the links are covalent, so the electrons are somewhat shared). If there is not a substance willing to take those electron, then why would the fuel react (burn)? Fuel will not react with another fuel, even a different type of fuel, as they both want to give their electrons away.

For the record, it does not have to be oxygen. You can have combustion with fluorine or chlorine or other substances with high electronegativity, but the other substances are not abundant in the atmospheres, so it is usually oxygen that does the oxidizing part.

Answer 2

I don't know how to word this in a scientific terms, so bare with me.

Oxygen is the source of life on the planet, right? Well, it is also needed for a fire to burn. You can't breath in a vaccum, because their is no air, it literally means there is nothing there. You would sufficate. Fire needs fuel to burn as well, fuel i.e. paper is only consumed because the oxygen is breathing life into the fire.

I'm a firefighter, and if it helps I can tell you that there are three stages to a fire:

The smodering stage 1: For example a cigarette is left sitting on a couch. The actual falmes have not started yet. Materials are heating up to the flash point of the materials on the couch.

Free Burning Stage 2: The cigarette has created enough heat, and has sufficant fuel to consume. Toxic gases and heat are forming not only around the objects burning, but the enitre room. These gases are heading for the ceiling because they are heavier than air, and oxygen. END OF STAGE TWO: every object and material in the room has reached it's falsh point( point where an object will ignite) and a FLASHOVER occurs. This means that the entire burts into flame.

Extinghment Stage 3: The fuel, and oxygen in the room has been depleted. The fire is starving(this occurs when the room it is burning in is relatively air tight.) It will be sucking the windows in the room in and out like it is really breathing. There will be no flame just a room filled enitrely with smoke, yellowish in color. If left alone it is possible that it could burn itself out. However if you aren't careful and open a door or window you will create a BACKDRAFT. This will create an explosion, that can move a foundation of a house, not to mention blowing out windows and doors.

I hope this is helpful in some way.

Answer 3

I was a firefighter and the first answerer gave the correct answer. You cant have fire if one of those elements are missing...Vapor from gas as you suggest will not replace the oxygen...Now fire would burn out the oxygen in the room and let say someone opened the door and there is still heat (need this to create a back draft), introducing oxygen, you will then have whats called a back draft which is not a pretty sight if you on the other end....

Answer 4

What we call "fire" is a chemical reaction combining oxygen with one or more other elements (carbon and hydrogen, in the case of burning gasoline, fuel oil, or other hydrocarbons).

There can be other similar chemical reactions, involving (for example) fluorine or chlorine, or even nitrogen.

Fluorine is the only element that is a more powerful oxidizing agent than oxygen. But since oxygen is plentiful in the atmosphere, whereas fluorine is not abundant anywhere, we talk about an "oxidation" reaction or an "oxidizing" agent.

Oxygen is the most active "oxidizing" element that is readily available, and when it reacts we call it "fire." So by definition fire requires oxygen. Other similar, violent chemical reactions are possible with other elements, but we don't call them "fire."

Answer 5

It is called a Fire triangle. It MUST have each of the three "sides"
1) Fuel (i.e. wood, gas, paper, etc)
2) Ignition (matches, sparks, lighter)
3) Oxygen source.

If any one of the three parts of the triangle are removed, the fire goes out.

BTW- SOmething like Potassium Permanganate (KMnO4) doesn't follow the rule. It creates its own oxygen source. And so can burn pretty much in the absence of Oxygen.

Answer 6

I believe this is right - fire is a rapid oxidation process, which requires oxygen. This is why the products of combustion contain oxygen, such as CO, CO2, NO2? - Rusting is a slow oxidation process by comparison.