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Mysterious hydrogen

  1. Jun 26, 2008 #1
    hi all,

    I was doing electrolysis to produce hydrogen. I start getting a gas that is so mysterious to my science knowledge. When i put fire into it, it eat up the flame and put out the lighter. AT first I thought that must be carbon-dioxide (fire extinguisher reagent). Then i put some soap into the surface of the solution and collect that gas in bubbles. When i put fire in it, it explode. I am convinced that it is hydrogen. This contradict to science that hydrogen is flamable. I read a government physics document said that the reaction of hydrogen and oxygen is a colorless flame. Then there must be a present of something that make hydrogen combust into a real visible flame in the air... It seems like hydrogen will be friendly to friendly element(thus produce so low temperature,colorless flame) and aggressive with aggressive element (metal) (produce a high temperature, visible flame) .
  2. jcsd
  3. Jun 26, 2008 #2
    It's likely that the major reaction you were seeing was the combustion of hydrogen gas. Hydrogen combusts pretty violently, often explosively (which is why balloons are no longer made of hydrogen). While it is true that pure oxygen-hydrogen flames emit light in the ultraviolet, impurities from the soap or water could have provided some trace elements which would be visible.


    http://www.theUndergraduateJournal.com [Broken]
    Last edited by a moderator: May 3, 2017
  4. Jun 26, 2008 #3
    It's incredible. I've seen video that hydrogen torch can melt anything. It also mysterious that the flame temperature get higher depends on the material. A normal torch cannot do that. I'm so excited to make hydrogen tomorrow. Hopefully at a rate to create a mini torch to melt stuff.
  5. Jun 26, 2008 #4


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    Science Advisor

    Hydrogen gas will be produced at the cathode (negative terminal).
    Noticeable more Hydrogen bubbles will be produced compared to the other gas which is generated at the anode (+).

    What that other gas is, the one generated at the anode, will depend on what electrolyte you are using. For example, if you have Chloride ions present in your solution (possibly from NaCl being your electrolyte) then you will get some Chlorine gas generated as opposed to only Oxygen.

    Hydrogen will burn extremely rapidly in air, and even more so if it is pre-mixed with an oxidizing gas (for example, Oxygen gas or Chlorine gas). It might be that igniting the Hydrogen bubbles is blowing out your lighter’s flame.

    When you trap Hydrogen in bubbles and ignite them you should hear a popping sound as they burn. If they are very small bubbles (like a foam, but not in that high of a concentration) then you might not heat so much, but if the bubbles are large then the popping sound can be surprisingly loud.
  6. Jun 27, 2008 #5


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    Staff: Mentor

    Just don't forget to be careful, if you don't want to land in the hospital. These explosions - when they get larger - can be quite dangerous.
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