When 1 mole of benzene is mixed with 1 mole of toluene, the vapours will contain

Step-by-step solution

Benzene is more volatile than toluene, which means the vapour pressure of pure benzene is greater than that of pure toluene ( P^ _B > P^ _T ). Given that 1 mole of benzene is mixed with 1 mole of toluene, the mole fractions in the liquid phase are x_B = 0.5 and x_T = 0.5 . According to Raoult's law, the partial pressures in the vapour phase are P_B = x_B P^ _B and P_T = x_T P^ _T . Since P^ _B > P^ _T and x_B = x_T , it follows that P_B > P_T . By Dalton's law of partial pressures, the mole fraction in the vapour p