We’re asked to **describe the relative strength **of **chloroform-acetone interactions** compared to the** acetone-acetone and chloroform-chloroform interactions** by **comparing the vapor pressure** of each** pure solvent** to that of the **solution**.

We can** compare the intermolecular forces **or interactions **between** the** molecules in the solution** and **pure solvent** by solving for the **vapor pressure of the solution.**

The given solution is composed of chloroform*CHCl _{3}* and acetone,

$\overline{){{\mathbf{P}}}_{{\mathbf{solution}}}{\mathbf{=}}\mathbf{\left(}\mathbf{P}{\mathbf{\xb0}}_{{\mathbf{CHCl}}_{\mathbf{3}}}{\mathbf{\chi}}_{{\mathbf{CHCl}}_{\mathbf{3}}}\mathbf{\right)}{\mathbf{+}}{\mathbf{\left(}}{\mathbf{P}}{{\mathbf{\xb0}}}_{{\mathbf{CH}}_{\mathbf{3}}{\mathbf{COCH}}_{\mathbf{3}}}{{\mathbf{\chi}}}_{{\mathbf{CH}}_{\mathbf{3}}{\mathbf{COCH}}_{\mathbf{3}}}{\mathbf{\right)}}}$

where P˚ = vapor pressure of pure component and χ = mole fraction of component.

Recall that the** mole fraction** is given by the equation:

$\overline{){\mathbf{\chi}}{\mathbf{=}}\frac{\mathbf{moles}\mathbf{}\mathbf{of}\mathbf{}\mathbf{solute}}{\mathbf{total}\mathbf{}\mathbf{moles}}}$

A solution contains 4.08 g of chloroform (CHCl_{3} ) and 9.29 g of acetone (CH_{3} COCH_{3} ). The vapor pressures at 35 ^{o}C of pure chloroform and pure acetone are 295 torr and 332 torr, respectively.

What can you say about the relative strength of chloroform-acetone interactions compared to the acetone-acetone and chloroform-chloroform interactions?

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 Solutions, Molarity and Intermolecular Forces concept. You can view video lessons to learn Solutions, Molarity and Intermolecular Forces. Or if you need more Solutions, Molarity and Intermolecular Forces practice, you can also practice Solutions, Molarity and Intermolecular Forces practice problems.

What professor is this problem relevant for?

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