🤓 Based on our data, we think this question is relevant for Professor Ratliff's class at USF.

We’re being asked to determine the **partial pressure of ethanol (C _{2}H_{5}OH)** above a solution. Recall that the vapor pressure of a solution can be given by

The given solutions are composed of ethanol and 1-propanol, which are both volatile. For a solution with volatile solute and solvent, Raoult’s Law is given as:

where P˚ = vapor pressure of pure component and χ = mole fraction of component. Recall that the ** mole fractions in a solution add up to 1**. Since the solution is composed of ethanol and 1-propanol, this means:

At 35°C the vapor pressure of pure ethanol (C_{2}H_{5}OH, M = 46.1 g/mol) is p_{E}° = 100.0 torr, and the vapor pressure of pure 1-propanol (C_{3}H_{7}OH, M = 60.1 g/mol) is p_{P}° = 37.6 torr. A solution at equilibrium at this temperature has a total pressure p = 84.2 torr. Assuming the solution is ideal, what is the partial pressure of ethanol above the solution?