Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Identity of an Unknown Liquid

  1. Oct 27, 2017 #1
    I performed a laboratory experiment using a Dumas bulb to find the molar mass of an unknown, clear liquid in order to identify it. The Dumas bulb was submerged in a beaker filled with water (with the tip out of the water) and the water was boiled to evaporate the sample.

    I eventually got a result with 38.1 g/mol as the mean, with a huge confidence interval (at 95%) of +- 18.1 g/mol. This is because I screwed up my 3rd trial so I could only use my first 2. I got results of 36.72, 39.56, and 49.11 g/mol.

    I need help identifying this liquid.

    The liquid is clear, safe to inhale in vapor form (I'm still alive), does not have a distinct smell, has a boiling point lower than 100 degrees C, and is not "an exotic compound".

    Edit: I'm now deciding between ethanol and methanol. I'm hearing that methanol is poisonous in vapor form, so I think it may be ethanol.
    Last edited by a moderator: Oct 27, 2017
  2. jcsd
  3. Oct 27, 2017 #2

    jim mcnamara

    User Avatar

    Staff: Mentor

    This appears to be lab homework, so moving the thread to homework section. No template.
  4. Oct 28, 2017 #3


    User Avatar

    Staff: Mentor

    These alcohols do have a quite characteristic smell.
  5. Oct 28, 2017 #4


    User Avatar
    Science Advisor
    Gold Member

    Methanol isn’t really any more poisonous than other common solvents. Of course, like most common solvents, if you drink it, that’s bad news, but simply smelling it is very unlikely to hurt you.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted