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Boiling Point of Isoprpoyl Alcohol Under a Vacuum?

Discussion in 'Concentrates' started by ghostslinger, Dec 5, 2012.

  1. ghostslinger

    ghostslinger Member

    Lost in research
    Hello FC!

    I've lurked for a while and decided to join today since I've got a question I can't answer with my level of knowledge.

    So I have a basic grasp of chemistry (emphasis on basic) but I'm having trouble calculating boiling points of isopropyl alcohol under a vacuum.

    I know it's 82.5℃ at 1 atm but when I try to use a boiling point calculator, I get NaN for the boiling point under different levels of vacuum. What am I doing incorrectly?

    Thanks ladies and gents.
  2. babemomlover

    babemomlover Member

    depends on what level of vacuum...
    P/T = P/T
    where first P, T, are atmospheric pressure and 82.5 degrees celsius converted to kelvin
    solve for second T, when second P is pressure in the vacuum and that's your bubble point temperature for Iso

    Edit: can solve for you if you give me your vacuum pressure
    ghostslinger, Quetzalcoatl and Tweek like this.
  3. ghostslinger

    ghostslinger Member

    Lost in research

    Thank you very much for the reply. I've been away from technology for a few weeks for reasons not of my own that I'd rather not discuss here, and so I apologize for the lateness of my reply.

    With the equation I've found the (theoretically sustainable) boiling point, but I've come into some problems with the actual evaporation (theory and reality, why must you be so different :( ).

    I'm essentially trying to evaporate the ISO from QWISO in a vial about 1/2 a dram in size. Naturally, I'm fighting surface area so I figured "Why not put it under a sustained vacuum?" Thankfully, I stopped right there since I doubt the vial could handle the pressure changes so quickly and also my solution would be sucked up into the hosing (which we all know is never a good thing).

    My latest question is: Would a stopcock and hose attached to the vial and vacuum enable me to have a controlled pull (via the key) and thus safely evaporate the iso out?

    Again, thanks guys for all the knowledge!

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