We know that for dry air, we have:
-78.08% mol N2 ;
-20.94% mol O2.
- Y(N2) = 0.7808 for nitrogen (the molar fraction in vapor)
- Y (O2) = 0.2094 for oxygen
Knowing that the Henry's law constants are:
for N2 and O2 are 6.51 x 10^7 Torr and 3.3 x 10^7 Torr, respectively
Calculate the mole fractions of N2 and O2 dissolved in water (xN2 and xO2) under total pressure of 1.000 bar
The partial pressure = henry's constant k1 x mole fraction of water (x)
P(N2) = K(N2).X(N2)
Same for O2.
Also, from Raoult's law:
Y(N2) = P(N2)/P(tot)
Same for oxygen.
The Attempt at a Solution
I tried applying the equations, but instead of the expected (x(N2)=0.6), I get really small results such as 0.00000651
I am just wondering if I am doing anything wrong by mixing the vapour molar fraction equation with Henry's law for the molar fractions for water?