In: Chemistry
Estimate the vapor pressure of ethyl ether at 40 degree celcius using the Clausius-Clapeyron equation based on the experimental values as follows. Remember that T in the Clausius-Clapeyron equation is absolute and pressure is in mmHg.
p* (mmhg) |
19.0 | 112.51 | 442.0 |
Temprature(degree celcius) | -40.0 | -10.0 | 20.0 |
From Classius Clapyeron equation the plot of lnP vs 1/T gives a straight line and the plot is shown below
the data on deg.c is converted to K by adding 273.15 and the data of lnP vs 1/T is
ln P 2.944 4.72 6.09
1/T 1/(-40+273.15) =0.004289 0.0038 0.003411
The plot is shown below and the equation for best fit is also given
The data satisfied the equation lnP (mm Hg)= -3586*1/T+ 18.33
at 40 deg.c = 40+273.15 =313.15 1/T= 1/313.15= 0.003193
lnP= -3586*0.003193+ 18.33 = 6.878
P = exp(6.878)= 971.28 mm Hg