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Hydrogen Discharge tube

  1. Apr 23, 2010 #1
    I experimented with a hydrogen tube and after some time the emission stopped.could it be because all hydrogen atoms became completely ionized?
  2. jcsd
  3. Apr 24, 2010 #2
    Could you describe this in more detail?
    What was the arrangement of your experiment? What was the purpose?
  4. Apr 24, 2010 #3
    the purpose was just to observe the spectrum using an induction coil. the tube was in operation about an hour and after that tha dark spaces were connected together and some time later the emission stopped.
  5. Apr 24, 2010 #4


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    Staff: Mentor

    I think it's because the hydrogen gas in the tube simply gets absorbed by the glass in the walls of the tube, or by the electrodes. It happens more easily with hydrogen than with other gases because the atoms/molecules are so light.

    In our introductory labs we use a variety of gas discharge tubes for observing spectra (hydrogen, helium, argon, neon, mercury). We have to replace the hydrogen tubes often because they "wear out" like this. The other tubes usually last until someone breaks them.
  6. Apr 24, 2010 #5
    but the concern is the fact that on the following day the hydrogen tube started emitting though the intensity was a bit weak.
  7. Apr 24, 2010 #6
    I have a vague memory of someone telling me that the tubes can be "regassed" by putting them in the fridge or freezer for a few hours.I don't know if it works.
  8. Apr 24, 2010 #7
    I browsed through the internet and did not find anything regarding your statement...wonder if it's true...when cooled atoms do slow down and wonder if it accelerates the recombination process....
  9. Apr 24, 2010 #8
    Are hydrogen tubes meant to be operated interminently? because i had turned it on for more than 10 minutes....
  10. Apr 24, 2010 #9
    I browsed as well and found nothing.:confused:
  11. Apr 25, 2010 #10
    here are some videos i took during the experiment ...

    Last edited by a moderator: Sep 25, 2014
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