At a given temperature the vapor pressures of hexane and octane are 183 mmhg and 59.2 mmhg, respectively. calculate the total vapor pressure over a solution of haxane and octane with xhexane = 0.580.

Total vapor pressure can be calculated using partial vapor pressures and mole fraction as follows:

Here, is mole fraction of A, is mole fraction of B, is partial pressure of A and is partial pressure of B.

The mole fraction of A and B are related to each other as follows:

In this problem, A is hexane and B is octane, mole fraction of hexane is given 0.580 thus, mole fraction of octane can be calculated as follows:

Partial pressure of hexane and octane is given 183 mmHg and 59.2 mmHg respectively.

Now, vapor pressure can be calculated as follows:

Putting the values,

Therefore, total vapor pressure over the solution of hexane and octane is 131 mmHg.