Colligative Properties of Nonelectrolyte Solutions

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To determine the grams of sucrose needed to lower the vapor pressure of 552 g of water by 2.0 mmHg, Raoult's Law can be applied, as this scenario involves a dilute solution. The vapor pressure of pure water at 20 °C is 17.5 mmHg, so the target vapor pressure for the solution is 15.5 mmHg. The calculation requires finding the mole fraction of sucrose that will achieve this pressure reduction. Additionally, it is important to follow forum guidelines and post in the appropriate section for homework-related questions. Understanding these principles is essential for solving colligative property problems effectively.
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How many grams of sucrose (C_{12} H_{22} O_{11}) must be added to 552 g of water to give a solution with a vapor pressure of 2.0 mmHg less than that of pure water at 20 ^ \circ C? The vapor pressure of pure water at 20 ^ \circ C is 17.5 mmHg.

This is one of many similar types of problems in Chemistry (7th ed.) by Raymond Chang.

I don't know how to start this. Does it involve Raoult's Law?
 
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Yes, (in the limit of a dilute solution) you can use Raoult's Law.

PS : Next time, such questions go in the appropriate section of the Homework/Coursework forum. And before posting there, please read the rules for posting (also found in the second line of my sig.)
 
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