Question

Which of the following statements about the composition of the vapour over an ideal 1 : 1 molar mixture of benzene and toluene is correct? Assume that the temperature is constant at 25°C. (Given, vapour pressure data at 25°C, benzene = 12.8 kPa, toluene = 3.85 kPa)

(a) The vapour will contain equal amounts of benzene and toluene.

(b) Not enough information is given to make a prediction.

(c) The vapour will contain a higher percentage of benzene.

(d) The vapour will contain a higher percentage of toluene

Answer 1

Correct option (c) The vapour will contain a higher percentage of benzene.

Explanation :

For an ideal 1 : 1 molar mixture of benzene and

Thus, the vapour will contain a high percentage of benzene as the partial vapour pressure of benzene is higher as compared to that of toluene.