Question

At 25 °C, the vapor pressure of acetone is 230 mm Hg, and the vapor pressure of

toluene is 28.4 mm Hg. A solution of these two miscible liquids having a 5:1 molar
ratio of acetone:toluene is at a temperature of 25 °C. What is the total vapor
pressure above this solution? Show your calculations for full credit.

Answer 1

To find the total vapor pressure above the solution, we can use Raoult's law. According to Raoult's law, the partial vapor pressure of a component in a solution is equal to its mole fraction multiplied by its vapor pressure in the pure state.

Step-by-step explanation:

To find the total vapor pressure above the solution, we can use Raoult's law. According to Raoult's law, the partial vapor pressure of a component in a solution is equal to its mole fraction multiplied by its vapor pressure in the pure state.

In this case, the mole fraction of acetone is 5/6 (since there is a 5:1 molar ratio of acetone to toluene), and the vapor pressure of acetone at 25 °C can be calculated using the Clausius-Clapeyron equation.

Using the given information about the boiling point and enthalpy of vaporization of acetone, we can calculate its vapor pressure at 25 °C to be approximately 179 mm Hg.