Problem: At 35 oC the vapor pressure of acetone, (CH3 )2 CO, is 361 torr, and that of chloroform, CHCl3, is 301 torr. Acetone and chloroform can form weak hydrogen bonds between one another; the chlorines on the carbon give the carbon a sufficient partial positive charge to enable this behavior:A solution composed of an equal number of moles of acetone and chloroform has a vapor pressure of 250 torr at 35 oC.What would be the vapor pressure of the solution if it exhibited ideal behavior?

FREE Expert Solution

We’re asked to determine the vapor pressure of an ideal solution composed of an equal number of moles of acetone and chloroform given the vapor pressure of each pure component


The given solution is composed of chloroformCHCl3 and acetone,CH3COCH3 which are both volatile


For a solution that exhibits ideal behavior with volatile solute and solvent, Raoult’s Law is given as:


Psolution=(P°CHCl3χCHCl3)+(P°CH3COCH3χCH3COCH3)


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 equal amounts of chloroform and acetone, this means:

99% (452 ratings)
View Complete Written Solution
Problem Details

At 35 oC the vapor pressure of acetone, (CH3 )2 CO, is 361 torr, and that of chloroform, CHCl3, is 301 torr. Acetone and chloroform can form weak hydrogen bonds between one another; the chlorines on the carbon give the carbon a sufficient partial positive charge to enable this behavior:
Acetone is a central C double bonded left to O and single bonded right, angled up and down, to two CH3s.
A solution composed of an equal number of moles of acetone and chloroform has a vapor pressure of 250 torr at 35 oC.

What would be the vapor pressure of the solution if it exhibited ideal behavior?

Frequently Asked Questions

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 professor is this problem relevant for?

Based on our data, we think this problem is relevant for Professor Smith's class at MSSTATE.