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Elements that cause explosion/burn

  1. Apr 20, 2007 #1
    As far a I know it's only the combination of Hydrogen, and Oxygen Atoms that cause explosion/burn, and that if there's other atoms in the mix it just causes a slower reaction. Is this true, if not then what other atoms cause explosion/burn?
  2. jcsd
  3. Apr 20, 2007 #2


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    "Burning" is typically what you call it when something combines in an exothermic reaction with oxygen and there are probably thousands of reactions that would qualify. One of the simpler ones that we use all the time is carbon combining with oxygen to form carbon dioxide. That's what coal is and where a portion of the energy from any hydrocarbon comes from.

    Most metals oxidize, for example. For iron, it is called rust, but the rection is still exothermic and the rates and energy released vary accordingly. Solid aluminum forms an imperceptibly thin layer of rust, but powedered aluminum is used as rocket fuel.
    Last edited: Apr 20, 2007
  4. Apr 20, 2007 #3
    are you sure that's what's causing most of the explosion though, because there are also H Atoms in Coal and when that burns it will combine with O. Also when pure H and O are burned it's interesting to note that they have an implosion effect, for instance you can weld wood to metal with this flame, and it will reduce radiation in a material.
  5. Apr 20, 2007 #4


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    No, coal is almost pure carbon.
    Huh? Sorry, but those words don't form a coherent thought. A lot of them don't belong in the same sentence with each other.
  6. Apr 20, 2007 #5


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    Yes, steam is less dense than hydrogen gas. I'm not sure if cooling of the steam has to occur before it's less dense.

    Anything under hydrogen in the periodic table, such as Sodium will have a much stronger reaction to Oxygen. Sodium can be tossed into water and the Sodium will break the Hydrogen / Oxygen bond and bond with the Oxygen itself, generating a lot of heat, enough that the released hydrogen will burn as it is released into the atmosphere.

    Potassium would be stronger still.
  7. Apr 21, 2007 #6
    @ russ

    I looked at the diagram on this page and that looks like plenty of H to cause a percentage of the burn.


    maybe that diagram not perfect, I dunno, I can't find better info on the coal molecule structure.

    H2 and O2 would explode to HH and OO before forming the water molecule
    H2O which would take up less space then what it was before, so there's probably imposion, after the explosion.

    People that make welders out of H2 and O2 (and not in the books/proven HHO) say it can weld wood to metal.

    here's a video of the radiation reduction of the gas, I just don't know why they would make the video if their equipment didn't read what they say it does.
    [crackpot link deleted]

    there's alos plenty of H in fuels, when that H is in an explosion it must go somewhere, right?
    molecular structure of fuels diagram
    [crackpot link deleted]
    Last edited by a moderator: Apr 21, 2007
  8. Apr 21, 2007 #7
    well here's the video that explains the implosion effect. sorry that it's bad quality.

    [crackpot link deleted]

    33.3% H and 66.6% O = implosion

    I do some experimenting with this gas myself, and follow many others experiments, I see signs of implosion in some bubbles I explode, bits of water blowing out the centre.
    Last edited by a moderator: Apr 21, 2007
  9. Apr 21, 2007 #8


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    A small percentage. Note that most of the hydrogen in coal is already tied up in water - it is already burned.
    Don't call the separation of H2 into 2 H an explosion. There is no energy released.
    As Jeff said, that would only be true if the temperature remained the same and it doesn't. If it were true, hydrogen wouldn't make such an excellent rocket fuel.
    I've never heard the claim and don't know the basis, so I can't evaluate it except in the context of the other claims you are airing here...
    That's just crackpottery.
    Yes, the most common fuels we use are hydrocarbons, which get their energy from the combustion of hydrogen and carbon in oxygen. Your original question was asking if hydrogen is the only thing that burns and the answer is a simple no.
    Last edited: Apr 21, 2007
  10. Apr 21, 2007 #9


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    I'm sorry, but that's just pure crackpottery. It is nonsense and we don't entertain discussions of such things here - it detracts from our mission of teaching science. Please be advised that we will not continue with discussion of that.

    If you have any more questions that are related to the OP, we will be happy to answer them.
    Last edited: Apr 21, 2007
  11. Apr 21, 2007 #10


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    I mentioned hydrogen gas. A typical rocket uses liquified hydrogen (and liquified oxygen), which is much denser than the steam produced from combustion. Liquified hydrogen / oxygen provide more energy per pound of fuel than any other combination I'm aware of.

    Explosive fuels:

    Hydrogen / oxygen, but unless liquified, it takes up a lot of space.

    Ethylene Oxide - used in Fuel Air bombs, obviously quite explosive.

    Gasoline - older fuel air bombs used gasoline.

    Aluminum, Magnesium, and other metals ground in to nano-fine dust.

    TNT and C4 of course.

    UN list of explosives by container requirements:


    Fun stuff, back yard experiment with Akali Metals:


    Hydrogen Peroxide 80% or purer, is one of those rare single "ingredient" fuels, it only needs silver to act as a catalyst. It's not the best amount of energy per pound of fuel, but it does have some semi-practical uses as in this video:

    Last edited: Apr 21, 2007
  12. Apr 21, 2007 #11
    Yes, but according the wikipedia page you posted, it only decribes the Carbon combining with the Oxygen to explain the explosion, but there's also Hydrogen in coal, and I am asking for compensation for all atoms in the reaction, the atoms must go somewhere.
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