Chemistry- Clausius Clapeyron Equation?
The heat of vaporization of water is 40.67 kJ/mol. What is the vapor pressure of water (in atm) at 25oC?
note: I THINK i did it. I got this crazy large number and I have no idea if I did it correctly.
- hcbiochemLv 74 weeks ago
The vapor pressure at 25 C should be much less than the vapor pressure at the boiling point, so perhaps you did something wrong
ln (p2/p1) = Delta Hvap/R (1/T1-1/T2)
You know that at 100 C( 373.15 K) the vapor pressure of water is 760 mm Hg. Using that as one point,
ln (p2/760) = (4.067X10^4 J/molK / 8.314 J/mol) (1/373.15 - 1/298.15)
p2 = 28.1 mm Hg