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How can I recreate this pressure boiling experiment

  1. Feb 24, 2016 #1
    Hi all,

    I was just wondering how I could recreate this at home
    What parts do I need?

    Thanks,
    Harry
     
  2. jcsd
  3. Feb 24, 2016 #2

    Vanadium 50

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    I'm afraid if you have to ask, you don't have the expertise to do this safely. Sorry.
     
  4. Feb 24, 2016 #3
    What are the safety risks?
     
  5. Feb 24, 2016 #4

    berkeman

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    Staff: Mentor

    Well normally pulling a vacuum involves an implosion risk. That jar is not a good vacuum enclosure. But the simple water pump mechanism being used in the video pulls a pretty mild vacuum, so the implosion risk is probably minimal.

    Get the water pump thing, and use epoxy to fasten a nipple onto a jar lid, I guess. I'm surprised that it takes such a soft vacuum to cause the water to evaporate like that.
     
  6. Feb 24, 2016 #5
    I was to, but some intelligent folks on here cleared it up for me; the vacuum caused by the aspirator is only limited by the vapour pressure of water. Basically, I need to get the pressure down to about 1kPa at room temp for evaporation to occur.

    I was mostly wondering what the tubing he uses is called so I could get my hands on some. Also, I plan to add another chamber where the evaporated water can collect.

    Thanks again all
     
  7. Feb 24, 2016 #6

    berkeman

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    Why did you create a second thread on the same subject? That is against the PF rules...
     
  8. Feb 24, 2016 #7
    I asked how I could recreate it here - In the other one I asked about how the pump works. Sorry if I broke the rules. You can ban me or whatever the punishment is. Thanks for the help.
     
  9. Feb 25, 2016 #8

    Borek

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    Take a syringe - the larger, the better. Suck a bit of hot water inside, plug the hole (even with a finger), pull the piston. Water will boil instantly, even if for a very short period of time. That's exactly the same effect.
     
  10. Feb 25, 2016 #9
    I need to do it on a bigger scale like in the video.
     
  11. Feb 25, 2016 #10

    DrDu

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    A water pump can get you near as low as the vapour pressure of water which is about 20 mbar while the outside pressure on the vessel is 1 bar.
    Hence the pressure difference acting on the vessel is nearly 1 bar which is all what counts in terms of implosion risk. Even with a high vacuum pump it won't be higher.
     
  12. Feb 25, 2016 #11

    berkeman

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    Staff: Mentor

    In that case, this thread is closed.
     
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