So I know oxygen loves to form bonds with things like carbon in biological materials to make co or co2 and all that and that combustion needs an oxidizer but when people talk about combustion they almost ALWAYS only mention oxygen, surely other elements csn do the same job as oxygen or replace oxygen in a normal fire for example? I also know for example flourine gas can oxidise better than oxygen and burn normsly inert material but I also had heard supposedly it still needed oxygen to BURN so which is it?
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Other elements can replace oxygen, or oxidize more strongly than oxygen, but those other elements aren’t a significant portion of the air around us.
For example, if you burn sodium metal with chlorine gas, the combustion product is table salt.
Yes, lots of things other than oxygen can be the oxidizer in redox reactions. A lot of them happen fairly slowly without giving off too much heat (rusting). Some happen very fast and can give off lots of heat. It just happens that hydrocarbons (wood, oil, wax, and other fuels) reacting with oxygen do it in a sustained way to make what we call fire. Other things are some combination of too slow, too fast, don’t give off heat and light etc.
Yes other chemicals can do the same job as oxygen, we call these substances oxidizers.
Sulfur, fluorine and chlorine as well as some molecules including them or oxygen are well known examples.
There are some scary substances that are so much better at doing the job that oxygen does that they can burn things already burned by oxygen.
You understand correctly that any oxidising agent (also known as electron acceptor or recipient) will combust when paired with any combustible material (known as fuel / electron donator) if there’s sufficient quantities of fuel, oxidising agent, heat and space for the resultant.
We normally only talk about oxygen because 21% of our atmosphere is oxygen, and 78% is nitrogen (which is basically inert), this means that in almost everyone’s sole experience with combustion, oxygen is involved as the only oxidising agent.
As for your main question, combustion is just a simple chemical reaction where the two materials make contact in a suitable environment and pair up, usually releasing more heat than what was needed to start the reaction.
A piece of wood is mostly carbon and water. The carbon is combustible and pairs up with oxygen to make CO and CO2, while the water steals heat and escapes as steam, without adding anything useful to the reaction
You can use other elements, or other chemical substances.
Fluorine, chlorine, sulphur, bromine, iodine all work as elements, and chemicals that contain them, like hydrogen peroxide, chlorine tetrafluoride etc.
The thing is, in day to day life, oxygen is everywhere, so if you have something that can oxidise, and is hot enough to do so, it will probably do so with oxygen.
Fluorine was used in a rocket engine prototype (burning hydrogen and lithium). The engine was very efficient, and very much on fire, but fluorine is very toxic and dangerous (it will displace oxygen, to the point of setting water on fire, creating oxygen and hydrogen fluoride gas, which then dissolves in water to create hydrofluoric acid).
Fluorine is so reactive it usually doesn’t stick around.
It’s a specialized type of oxidation/reduction (RedOx) reaction, so something needs to be getting oxidized and something needs to be getting reduced. the equation is
CxHy (usually) + O2 -> CO2 + H2O + heat
In this case, carbon is being oxidized and oxygen is being reduced. Oxygen is handy because it exists naturally in earth’s atmosphere and it’s a strong oxidizing agent. You can have other redox reactions with other oxidizing agents, you can even have combustion with other oxidizing agents, but you need an oxidizing agent to perform a redox reaction and we have plenty of O2 floating around in the air.