If 0.580mol  of a nonvolatile nonelectrolyte aredissolved in 3.50mol of water, what is the vapor pressurePH2O of the resulting solution? The vapor pressure of purewater is23.8 torr at 25 ?C .
In solutions composed of two liquids (A and B), each liquidcontributes to the total vapor pressure above the solution. Thetotal vapor pressure is the sum of the partial pressures of thecomponents:
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A 2.500×10^-2M solution of NaCl in water isat 20.0?C. The sample was created by dissolving a sample of NaCl inwater and then bringing the volume up to 1.000 L. It was determinedthat the volume of water needed to do this was 999.3mL . Thedensity of water at 20.0?C is 0.9982 g/mL.
a)Calculate the molality of the salt solution.
b)Calculate the mole fraction of salt in this solution.
c)Calculate the concentration of the salt solution in percent bymass.
d)Calculate the concentration of the salt solution in parts permillion.
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Atmospheric pressure is 1.01 bar, but air is only composed of21.0% (by moles) oxygen. Thus, the partial pressure of oxygen inair is less than 1.01 bar. What is the millimolar concentration ofdissolved oxygen for a lake or stream under the partial pressure ofoxygen and a temperature of 16?C?
