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Surface tension of water against a gas not being air

  1. Sep 8, 2010 #1
    Surface tension is a property of two different substances. The surface tension of water against air under different conditions is given in many textbooks and data handbooks. However, if the air is replaced by, say, hydrogen, what will be the surface tension? Where will I have to look for the answer?

  2. jcsd
  3. Sep 8, 2010 #2

    Andy Resnick

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    Interfacial energy measurements can be tough to find in the literature. To your specific question, one problem with performing measurements on water with various gases (or vacuum) is the vapor pressure of water- some will evaporate, contaminating the gas/vacuum. Consequently, there is a lot more data on mercury which has a much higher vapor pressure and does not evaporate.


    Sometimes, you will come across a paper with tables of this kind of data- I used to have one for various materials against dry air. If you do, please post it since I would like to have that data easily available as well!
  4. Sep 8, 2010 #3
    Andy, thank you very much for your input. I will continue to search for some relevant litterature.

    I have the feeling that replacing air with hydrogen does not make a big change to the surface tension. Can anyone tell whether this is correct. If it is correct, then why?

    Last edited: Sep 8, 2010
  5. Sep 8, 2010 #4

    Andy Resnick

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    Good question- I don't know. There's too many unknowns: the solubility of hydrogen in water, for example. I do know that the interfacial energy of water is pathologically sensitive to contamination, which makes precision measurements difficult.

    Girifalco and Good have some papers where they attempt to calculate the interfacial energy from first principles; these came out in the 60's and 70's. I couldn't make heads or tails of it, tho.

    Adamson's book "Physical Chemistry of Surfaces" is an excellent resource.
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