Naked Science Forum
Non Life Sciences => Chemistry => Topic started by: thedoc on 05/12/2016 16:36:22
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Why doesn't water burn?
(Mod edit: I deleted this post so I wouldn't have to scroll through it...)
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The name "Hydrogen" described the most startling property seen, back when this gas was first discovered:
- Hydro: Water
- Gen: maker
- Hydrogen makes water
Hydrogen makes water when it burns, by reacting with the oxygen in the air.
Water is what happens after the fire goes out - it is already 100% burned, and can't burn any more.
In more detail:
- Oxygen has two sites that can join onto another atom
- Hydrogen has one site that can join onto another atom
- The chemical formula of water is H2O, with 2 Hydrogen atoms and 1 Oxygen atom
- In Water, Oxygen has its two binding sites joined to a Hydrogen
- In water, each Hydrogen has its single binding site joined to an Oxygen
- The resulting Water is chemically very stable.
The only way it will burn is if you add another chemical that grabs the oxygen or Hydrogen even more strongly than they grab each other.
- One such chemical is the extremely reactive metal Sodium
- Sodium grabs the Oxygen atom out of the water, liberating the Hydrogen, which immediately catches fire, producing water again.
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Simply, water is already the ash you get by burning hydrogen, and ash doesn't burn.
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It actually does given the right circumstances see hydrogen fires.
And ash does burn in the right circumstances (see incinerator)
it all comes down to the fact that burning or combustion is the act of reacting with oxygen and only things that can react with oxygen will burn..
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It actually does given the right circumstances see hydrogen fires.
And ash does burn in the right circumstances (see incinerator)
it all comes down to the fact that burning or combustion is the act of reacting with oxygen and only things that can react with oxygen will burn..
Hydrogen fires make water- they don't burn it.
Incinerators make ash- they don't burn it.
It's possible to burn things in gases other than oxygen- fluorine is particularly good at it.
You can burn teflon in fluorine, but not in air.
Incidentally, does anyone know what has happened with teh formatting of this thread?
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yeah its a pain in the proverbial.
Incinerators make sure what ash you have is truly incombustible.. (solid oxides etc)
Hydrogen fires, are the only way to burn water, by splitting the hydrogen and oxygen and then burning the hydrogen again.. which yeah is splitting hairs.
Its all chemical reactions when it comes down to it anyway, I am sure you could burn stuff in all the reactive gases if you tried hard enough.
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Hydrogen fires, are the only way to burn water, by splitting the hydrogen and oxygen and then burning the hydrogen again.. which yeah is splitting hairs.
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That's not what happens in a hydrogen flame. Essentially all the hydrogen gets burned to water.
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Sorry, I work at sea, and there is a chance that if our boilers are leaking and emitting too much water vapour through the stack that we have fires caused by this water, which we call hydrogen fires. which as you point out is NOT the same as hydrogen flame.
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God knows what you have, but it's not burning water.
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Sorry, I work at sea, and there is a chance that if our boilers are leaking and emitting too much water vapour through the stack that we have fires caused by this water, which we call hydrogen fires. which as you point out is NOT the same as hydrogen flame.
Okay, After a little research, I found out what is happening with your "hydrogen fire". Under really high temperatures (+1000C) the water vapor in the stack will chemically combine with the soot in the stack forming H2 and CO which are both inflammable.
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Okay, After a little research, I found out what is happening
Thanks for doing Sailor's research for him
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Thanks :)
Never really thought too hard about it really, just blindly accepted what I was told.. (bad scientific practice!)
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One of the reasons water is the ideal solvent for life is because water does not burn. Water is a stable energy floor. If we used an alcohol or another other organic solvent, to evolve life, almost all these solvents contain potential energy and can burn. Life would eventually learn to burn its own solvent for food energy. But with water, life can't burn the water any further. Water will allow life to overcome the solvent burning chokepoint of other solvents, so life can keep progressing.
At the macro-scale water does not burn and is very chemically stable. However, if you look at water at the nanoscale, it is very dynamic. For example, a H2O molecule, in the liquid state, will only exist for about 1 millisecond before it trades it hydrogen for new hydrogen. This constant breaking and making covalent bonds is connected to hydrogen bonding and conversion of hydrogen bonds to covalent bonds or vice versa. Water is a dynamic environment at the nanoscale.