For an equimolar solution of n-pentane and n-hexane

[missmaria]

Question:
For an equimolar solution of n-pentane and n-hexane, compute:
a) dew-point pressure at 120 F
b) bubble-point temperature at 1 atm
c) the vapor fraction at 120 F and 0.9 atm, and the mole fractions of the vapor and liquid phases

My attempt at a solution:
I calculated the saturation pressures of both pentane and hexane, 1.52 and 0.51, respectively. Now i don't know what to use for xi and yi. I think i need to compute the K value, but still, i am stuck. Can anyone help? thanks!

 

[CaptainPanic]

I think that the law of Raoult is the one you want to use... but I am not certain that you have enough data for question c). I'd expect a volume and a total amount of solution given there.