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

Hydrogen bond

  1. Mar 18, 2005 #1
    i'm writing a lab report of an experiment investigating strenth of hydrogen bond. An excess of cyclohexane was mixed with ethanol and there's a decrease in temperature of the mixture. I was told that upon the addition of cyclohexane, the H bonds between ethanol molecules were broken and I don't know why. C of cyclohexane are probably not electronegative enough to give the H directly bonded to them a delta +ve charge to attract lone pair electron of O from ethanol. Van der Waal's forces between molecules of ethanol and cyclohexane are not strong enough to overcome the H bonds. Can anyone explain to me what had cyclohexane done on the ethanol molecules?? thx a lot~
  2. jcsd
  3. Mar 18, 2005 #2


    User Avatar

    Staff: Mentor

    I would bet on dilution.

    Chemical calculators for labs and education
    BATE - pH calculations, titration curves, hydrolisis
  4. Mar 18, 2005 #3


    User Avatar
    Science Advisor
    Homework Helper

    Tis an example of negative deviation from Raoult's law. Cyclohexane is interposed between the ethanol molecules reducing the degree of hydrogen bonding...note the difference between intramolecular hydrogen bonding and intermolecular hydrogen bonding.
  5. Mar 19, 2005 #4
    I haven't learnt this law. Can you say more about it??
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook