the simple answer is that H2O is not a compound…therefore it cannot be turned into carbon!!
jeepers some ppl babble on!!
and some make no sense 
Because fire and water are elemental opposites. To burn, a substance must contain a minimus of fire in its makeup, which water, being a pure element, does not.
(If you want an answer from later than the sixteenth century, you could see those who responded before me, but I stand by my answer.)
Ummmm…Chas? Do you know the difference between boiling/evaporation and burning? When liquid water changes to water vapor, it is NOT burning. Think about this for a minute.
Yes, I was a chem major in college (a long time ago). Do you know the difference between evaporation and sublimation?
Ask any winter camper what happens if you try to melt some snow in a pot over too high a heat. It will scorch and blacken.
Get a spray bottle and spray a mist of water over a hot gas barbecue. The flame has enough energy to knock the hydrogen and oxygen atoms out of the molecule, and it results in a huge flareup.
Chas.E said
Does a long time ago, when you were in college, mean some time in the dark ages? Burning is reaction with oxygen. Water does not react with oxygen. A flame could cause ionisation of water molecules if sufficiently hot. If that is what you were really taught, I am stunned.
Good ones!
I read an article in the Wall Street Journal a couple of years back about a group of arsonists who were using jet fuel to start fires. Apparently when the fuel burned it was so hot that when firefighters got there and sprayed water on the fire it would break the water down into Hydrogen and Oxygen and simply aggravate the situation. (I’m not sure if you can call that water burning.) Does anybody else remember this?
- Peter Wiggen
Um, isn’t this because the moisture causes the fat to splatter, mix with air, and combust? Isn’t the water just acting as a mechanical catalyst?
**Chas.E **said
android209 *responded with *
I went to school in Louisiana. I am not at all surprised. android209, were your teachers always right? I had some excellent teachers and others that…Well, let’s just say I’m not surprised.
Breaking water down into hydrogen and oxygen would absorb as much energy as would be released by burning hydrogen to produce water. So, I don’t see how this would make it worse. Could it be by spreading the fire, not producing more energy.
I don’t have a site handy, but regarding the burning jet fuel, this is why you don’t use water on oil fires! The water just spreads the fire, and if conditions are right, it can cause the FUEL to vaporize and then produce a free air explosion.
Goggle on those three words to learn about homemade bombs.
The water doesn’t separate and then recombine to form a larger fire. As DrMatrix said, that’s a zero net energy reaction.
OK, the reason you don’t use water to put out oil fires. Oil is lighter than water, it is also polar and won’t mix with the water…so the oil floats on top of the water, still in contact with the oxygen, so it continues burning. The water can also cause the fire to spread, boiling water causing splatters of burning oil everywhere. But the water does not burn, it can boil, but it can’t burn.
Chas: Sublimation is not the same as evaporation/boiling. Sublimation is the change from a solid directly into a gas, without passing through a liquid stage. CO2 works this way…solid CO2 doesn’t melt, it changes directly into gaseous CO2. Ice will often sublimate in very dry climates. I grew up in Fairbanks Alaska, and the icicles on the houses would always sublimate away even though the temperatures were always below freezing, the snow pack would thin out, etc.
Now, it may be that a very very hot fire can dissociate 2H20 into 2H2 + O2…but that would absorb energy, not liberate it. It takes electrical energy to electrolyze water into hydrogen and oxygen gas, right? But anyway, splitting water isn’t burning it, but the opposite of burning it, since the hydrogen you generate will burn. But then why doesn’t the water put out the fire?
Well, if the fire is hot enough, the water will boil instantly and rise, and won’t keep oxygen from the fire, which is why you usually put out fires with water. So what happens when you spray your campfire with water? It does release a bunch of energy, because you are transfering a lot of heat in the wood, rocks, metal, etc, into the air…you feel a burst of heat, just like when you pour water over hot rocks in a sauna. The total amount of heat is the same, but you’ve transfered it from the rocks to the air, where it is transfered to you.
And if your pot scorches when you try to melt snow…um, it isn’t the snow that burns! It could be the pot burning, or it could be that unburned fuel gets deposited on the pot. But the snow doesn’t burn, that’s silly!
Ak! I mean, oil/jet fuel is non-polar! Water is polar, and the two won’t mix. Sorry for the mix-up.
Chas, You have given me a great new excuse for when I screw up and burn things while cooking. “It wasn’t my fault, the water must gotten charred somewhere”
Organic substances turn black when they burn because incomplete combustion leaves some elemental carbon behind. If water burned it would not turn black because water doesn’t contain carbon. Something organic in the snow is burning, not the snow itself.
If you were a chem major in college you’ll remember that energy is gained by forming bonds not breaking them. Knocking atoms out of a molecule always requires the input of energy. For there to be a release of energy some new compound must form that has more stable bonds in it than water does. I can’t think of anything in a barbecue flame or in the atmosphere that would combined with oxygen and hydrogen in this way. If you do then I’d be interested in hearing about it. I suspect the flare-up is the result of air in the spray being injected into the fire.
The reason water won’t burn in a nutshell:
Flourine has the highest electronegativity of any element, Oxygen is a close second. Therefore, if you form a bond with oxygen, you are in the lowest possible energy state, unless you have a bunch of flourine sitting around. But we don’t have a bunch of flourine sitting around, due to quirks of nuclear fusion it is a much less common element in the universe than oxygen. You could “burn” water with flourine, but where are you going to get the flourine? Damn those pesky laws of physics!
OK, blackened snow…I’m thinking this could happen because snow is such a good insulator…not much heat gets transfered from the pot to the snow, so the pot blackens like an empty pot would. But this explanation strikes me as un-straight-dope-like…I really should get a pot of snow and try to melt it over a campfire and see what happens, but unfortunately it is August and there isn’t any snow here…