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Dry ice substituting for liqud nitrogen?

  1. Dec 15, 2005 #1
    Liquid Nitrogen and Dry Ice

    Hi I am doing an experiment for my chemistry independent project which is on doing super conductors, well i am doing one wherre you take YBa2Cu3O7 - the so-called "1-2-3" superconductor and put it in liquid nitrogen and it makes a rare earth magnet levitate above it, well i have the yittrium barrium copper oxide but i am having trouble getting liquid nitrogen as my school does not have a container to hold it. So i was wondering if dry ice can be substituted instead of liquid nitrogen as the school can get that easily. Thanks!
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  3. Dec 15, 2005 #2


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    At temperatures below 195 K (-78 °C), carbon dioxide condenses into a white solid called dry ice.

    Liquid nitrogen = 63.15 K (-210.00 °C, -346.00 °F).

    The record for maximum Tc is still held by a cuprate perovskite material (Tc = 138 K, that is −135 °C), so dry ice is not cold enough.


    Perhaps one could make arrangements with a local university physics/chemistry department, one that has a cryogenics facility.
  4. Dec 15, 2005 #3
    Dry ice isn't anywhere near cold enough to get the YBa2Cu3O7 to the superconducting temperature, which I think is somewhere around 90K. Dry ice, by contrast, is around 195K. You're going to have to get some LN2.

    Have your teacher contact a local university physics or chemistry department. They would probably be willing to lend some LN2 and a suitable container.
  5. Dec 15, 2005 #4


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    Hospitals, welding supply companies --- you might get lucky and find someone willing to donate time and material.
  6. Dec 15, 2005 #5


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    LN2 really isn't that expensive or difficult to transport in small amounts. My dad used to bring home 30 gal jugs of it to give demos for schools. See if you can find someone who works for an industrial gas company - or someone who uses a lot, like Bystander suggested.
  7. Dec 15, 2005 #6
    Minor quibble - that's the melting point of nitrogen. The boiling point is 77K.
  8. Dec 15, 2005 #7


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    That's what he was referring to, the melting temperature (he was referring to the solid form).

    Any biology department is also likely to have people with liquid nitrogen on-hand. It's frequently used to rapidly freeze and store cells or tissues.

    Be very careful when using it...you don't want to get ANY on your skin, because it will freeze skin immediately. Wear proper safety goggles and use tongs or some other holder to handle anything being placed in the liquid nitrogen.
  9. Dec 16, 2005 #8
    Another place you can find liquid nitrogen is at a tire recycling plant.
  10. Dec 16, 2005 #9


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    You are correct - my mistake. Nuts!!!!

    It should be the boiling point. 77.36 K (-195.79 °C, -320.42 °F)
  11. Dec 18, 2005 #10
    It would be a nice experiment using Liquid Nitrogen on Pyrolytic Carbon, Which already levitates on strong Magnets at room temperature.

    I have heard no word of its properties at Liquid Nitrogen Temperatures.

    I smell a Noble Prize around here somewhere.:smile:
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