At a given temperature the vapor pressures of benzene and toluene are 183 mm Hg and 59.2 mm Hg,respectively.Calculate the total vapor pressure over a solution of benzene and toluene with X_benzene = 0.580. A)106 mm Hg B)121 mm Hg C)131 mm Hg D)242 mm Hg

Question

Quizplus · Accepted Answer

The total vapor pressure, PT, can be calculated by using the equation:

PT = Xbenzene*Pbenzene + Xtoluene*Ptoluene

where Xbenzene and Xtoluene are the mole fractions of benzene and toluene, respectively, and Pbenzene and Ptoluene are the vapor pressures of pure benzene and pure toluene at the given temperature.

We are given Xbenzene = 0.580, Pbenzene = 183 mm Hg, and Ptoluene = 59.2 mm Hg.

So, substituting into the equation we get:

PT = 0.580*183 + (1- 0.580)*59.2 = 106.02 ≈ 131 mm Hg

Therefore, the best choice is C.

At a Given Temperature the Vapor Pressures of Benzene and Toluene