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Calculating Vapor Pressure problem

  1. Aug 23, 2009 #1
    1. The problem statement, all variables and given/known data
    A handbook lists the normal boiling point of isooctane, a gasoline component as 99.2°C and its enthalpy of vaporization as 35.76 kJ/mol. Calculate the vapor pressure of isooctane at 25°C.

    2. Relevant equations
    The only equation that makes sense to use for me is the Clausius-Clapeyron equation:
    ln(P2/P1) = (Hvap)/R * (1/T1 - 1/T2)

    3. The attempt at a solution
    Since I don't have either P2 or P1, how can I solve this problem?
    Should I just isolate (P2/P1), and solve?
  2. jcsd
  3. Aug 23, 2009 #2


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    What does "boiling point" mean in terms of vapor pressure?
  4. Aug 23, 2009 #3
    I think I got it. The vapor pressure should equal to 1 atm since boiling point is the temperature where the vapor pressure equals the surrounding's pressure or the atmospheric pressure. Thanks a lot!!!!!!!
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