chemistry - vapor pressure
posted by billy on .
the vapor pressure of pure water at 25C is 23.8 torr. determine the vapor pressure (torr) of water at 25 C above a solution prepared by dissolving 35g of urea (a nonvolatile, non-electrolyte, MW = 60.0G/MOL) IN 76G of water.
i just want to know the steps bc im confused... help?
Step 1. Determine mole fraction water.
a. moles urea = grams/molar mass = 35/60 = 0.583
b. moles H2O = 76/18 = 4.222
c. total moles = 4.805
d. XH2O = 4.222/4.805 = ??
Psoln = Xsolvent*Posolvent
where Po = normal vapor pressure of the solvent.
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