(ii) Total vapour pressure over the solution varies linearly with the
mole fraction of component 2 (iii) Depending on the vapour pressures
of the pure components 1 and 2,
total vapour pressure over the
solution decreases or increases with
the increase of the mole fraction of
component 1 A plot of p1 or p2 versus the mole
fractions x1 and x2 for a solution gives a
linear plot as shown in Fig 1