Oxygen

[fire vs. water]

I have a rather odd question, which I can't find an answer to.
How come oxygen is the/an oxidisier (it sounds funny, because the word "oxidiser" comes from the word "oxygen")?

I mean, right there's the fuel and there's the oxidiser?
Why is the oxygen preticulary been naturally chosen to be the oxidiser?
What special quality\property does it have, that Hydrogen, or Nitrogen (for example) don't have?

I hope I made myself clear.

[vulture]

An oxidizer oxidizes another material by reducing itself.
That basically means the oxidation state of the oxidizer goes down and that of the reducer goes up.

Now, because oxygen is the 2nd most electronegative element, it'll be the most stable in a negative oxidation state, which implies it should be reduced to -2 starting from 0. To do that it has to gain electrons from the reducer.

[THErAPIST]

It may be that I'm pretty tired... But are you trying to ask why things require the presence of oxygen to burn, and why things don't need hydrogen or nitrogen or something similar instead of oxygen?

[Ammonal]

Do I think that youre question might have been answered if you had done year 7 science? just kidding ;) If I remember a bit of high school chemistry there was a memory jogging saying "oxidation is a loss of electrons and reduction is a gain" your oxygen is classed as an oxy'DISER' because it removes or allows for the removal of electrons from other elements or compounds which means that it is gaining electrons and being reduced.
Flame away for anyone who disagrees with what my chem teacher told me!

[apathyboy]

Well, oxygen is just a powerful oxidizing agent. It removes electrons from other elements and forms compounds (oxides) with them. As previously mentioned, an oxidizing agent is just something that will accept electrons. Other highly electronegative elements like fluorine can act in the same way: steel wool could be said to "burn" (become oxidized) in fluorine, but burning is a term usually restricted to reactions with oxygen.

This is just speculation, but I think oxygen is the universal oxidizer because it forms relatively unstable groups with a high percentage of O atoms in them, like ClO4- and NO3-. These give off a lot of energy when burned with a fuel.

[fire vs. water]

Thanks for the help, but I don't really think anyone understood what I'm asking (my fault, not yours... ;) )

vulture I don't completly understood what you said, (this is my first year learning chemistry by the way).
Are you saying the oxygen has a -2 charge after it oxidizes something?
But doesn't sulfur also have a -2 charge in its ionic form?

"it'll be the most stable in a negative oxidation state" - although it's the most stable, oxygen is the only "oxydizer", how come there aren't any other materials that can be used as oxydizers?

---------------------------------------------

I'm sorry, I can't really explain myself well,
The question I'm asking is similar to "why do humans perticulary need oxygen in order to, and not hydrogen, for example?"

For that question I can find an answer, but for my question above, I cannot.

[T_Pyro]

Oxidation state of an atom in a compound is the apparent charge it appears to have in the compound, whether ionic or covalent. This definition might not be the most accurate, but it's the simplest one I could come up with. There are additional rules for assigning oxidation states in compounds, you should read up on them, too.

Like Vulture stated, oxygen is the second most electronegative element, so it'll be the most stable in the lowest oxidation state possible. (-2) Hypothetically, Fluorine could be used as an oxidiser, but there are other advantages of using oxygen- it's more abundant, and is less corrosive in its free state. Actually, OF2 is a very good oxidiser, and has been used as rocket fuel before.

Yes, sulfur has a -2 charge in metallic sulfides. However, the change in enthalpy of a reaction like Fe+S -> FeS is not too great to be of any use. This reaction requires quite some amount of energy to start out with (activation energy), but once the reaction proceeds, the heat generated makes the reaction mixture glow red-hot.