How many grams of sucrose (C12H22O11) must be added to 552 g of water to give a solution with a vapor pressure 2.0 mmHg less than that of pure water at 20 degrees C? (The vapor pressure of water at 20 degrees C is 17.5 mmHg.)(adsbygoogle = window.adsbygoogle || []).push({});

I tried it out, and this is my work.

change in P=mole fraction*P in degrees

2.0mmHg=X(17.5mmHg)

X=0.11 moles

552 g H2O * 1 mole/18.02g = 30.3 mol

0.11(30.3 + x)=30.3

3.33+0.11x=30.3

x=245.18 mol

245.18 mol sucrose * 324.34g/1 mol=83000

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# Homework Help: Colligative Properties

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