# Problem: Glycerin, C3H8O3, is a nonvolatile liquid. What is the vapor pressure of a solution made by adding 164 g glycerin to 338 mL H2O at 39.8°C? The vapor pressure of pure water at 39.8°C is 54.74 torr and its density is 0.992 g/cm3.

###### FREE Expert Solution

Vapor Pressure Lowering is a colligative property which describes the decrease in vapor pressure of a solution when a solute is added to a solution.

The formula for vapor pressure lowering is:

$\overline{){{\mathbf{P}}}_{{\mathbf{solution}}}{\mathbf{=}}{{\mathbf{\chi }}}_{{\mathbf{solvent}}}{\mathbf{·}}{\mathbf{P}}{{\mathbf{°}}}_{{\mathbf{solvent}}}}$

Where:

Psolution is the vapor pressure of the solution

solvent is the vapor pressure of pure solvent

Xsolvent is the mole fraction of the solvent

Solve for the mole fraction of the solvent:

$\overline{){{\mathbf{\chi }}}_{{\mathbf{solvent}}}{\mathbf{=}}\frac{{\mathbf{mol}}_{\mathbf{solvent}}}{\mathbf{\iota }\mathbf{·}{\mathbf{mol}}_{\mathbf{solute}}\mathbf{+}{\mathbf{mol}}_{\mathbf{solvent}}}}$

96% (322 ratings) ###### Problem Details

Glycerin, C3H8O3, is a nonvolatile liquid. What is the vapor pressure of a solution made by adding 164 g glycerin to 338 mL H2O at 39.8°C? The vapor pressure of pure water at 39.8°C is 54.74 torr and its density is 0.992 g/cm3.

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What scientific concept do you need to know in order to solve this problem?

Our tutors have indicated that to solve this problem you will need to apply the The Colligative Properties concept. You can view video lessons to learn The Colligative Properties. Or if you need more The Colligative Properties practice, you can also practice The Colligative Properties practice problems.

What textbook is this problem found in?

Our data indicates that this problem or a close variation was asked in Chemistry: An Atoms First Approach - Zumdahl Atoms 1st 2nd Edition. You can also practice Chemistry: An Atoms First Approach - Zumdahl Atoms 1st 2nd Edition practice problems.