Q.
The vapour pressure of two liquids ′P′ and ′Q′ are 80 and 60 torr respectively. The total vapour pressure of solution obtained by mixing 3 mole of P and 2 mol of Q would be
Mole fraction of P=3+23=53
Mole fraction of Q=3+22=52
Hence, total vapour pressure = (Mole fraction of P× Vapour pressure of P)+( mole fraction of Q× Vapour pressure of Q) =(53×80+52×60)=48+24 =72 torr