# The vapour pressure of pure liquid X and pure liquid Y at 25°C are 120 mm Hg and 160 mm Hg respectively. If equal moles of x and y are mixed to form an ideal solution, calculate the vapour pressure of solution

**Solution**

Vapour pressure of solution =

*P*

_{s}= ${P}_{X}^{0}{{\rm X}}_{X}+{P}_{Y}^{0}{{\rm X}}_{Y}$Since equal moles of X and Y are mixed, let mole fraction of X and Y be 0.5 each.

Putting the given values, we get

*P*

P60 + 80 = 140 mm Hg

_{s}= $120\left(0.5\right)+160\left(0.5\right)$P

_{s}=
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