How Does Raoult's Law Apply to Calculating Vapor Pressure in Solutions?

AI Thread Summary
Raoult's Law states that the vapor pressure of a solution is equal to the mole fraction of the solvent multiplied by the vapor pressure of the pure solvent, assuming non-volatile solutes. The discussion centers on a homework problem where the user compares their solution with the professor's. It is noted that the professor incorrectly used the mole fraction of the solute instead of the solvent, leading to an error in the calculation. The consensus is that the user's approach aligns correctly with Raoult's Law. Accurate application of Raoult's Law is crucial for determining vapor pressure in solutions.
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Homework Statement



http://i.minus.com/juL6gvGzvWdm.png

Homework Equations



Raoult's law: Pressure of solution = Mole fraction of solvent multiplied by vapor pressure of pure solvent. We're assuming non-volatile solutes.

The Attempt at a Solution



My solution:

https://scontent-b-mia.xx.fbcdn.net/hphotos-prn1/v/556873_10201073170213135_1235629214_n.jpg?oh=a01e718c3f2218dc3d130fd0007be82b&oe=528964FD

Prof's solution:

http://i.minus.com/jbtmawYMvRpDpX.png

Who's right?
 
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I agree with your answer.
 
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Yeah, it seems as if he used the mole fraction of the solute instead of the mole fraction of the solvent, which is a major boo-boo.
 
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