Solution:
When the last droplet of liquid is vapourized, the composition of vapour formed will be (given composition of the liquid solution).
Hence,
i.e.
Solving for , we get .
The pressure of the vapour will be
The mole fraction of liquid A in a binary liquid solution of and is 0.6. The pressure at which last droplet of liquid is vapouried and the mole fraction of A in this last droplet, respectively, are
When the last droplet of liquid is vapourized, the composition of vapour formed will be (given composition of the liquid solution).
Hence,
i.e.
Solving for , we get .
The pressure of the vapour will be