Chemical Forums
Chemistry Forums for Students => High School Chemistry Forum => Topic started by: sugarhillave on February 06, 2005, 08:07:17 PM
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in a soultion of sodium chloride in water, the vapor pressure is 19.6 torr at 25 degrees C.
i converted the pressure to 298.15 K and the temperature to .0258 atm.
i need to find out the mole fraction of NaCl, but i dont understand how to get either grams of moles.
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Maybe your thinking too much about moles and mass.
Try looking at water's vapor pressure. Since you started with C and torr, I'll stay with those units. At 25 C, pure water has a vapor pressure of 23.8 torr.
In your problem, the salt water solution has a vapor pressure of 19.6 torr.
Why did the vapor pressure change? If you can answer that, you should be on your way to the correct answer.