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Increasing vapor pressure in water

  1. Sep 8, 2009 #1
    Why does adding salt to water increase the vapor pressure? Does increasing the volume of water increase the vapor pressure?
  2. jcsd
  3. Sep 8, 2009 #2


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    Adding salt to water decreases the vapor pressure of the solution.

    No, vapor pressure is independent of volume. First, you need to consider the main thermodynamic driving force for the conversion of liquid water to gaseous water. Is this process driven by water seeking a lower potential energy (enthalpy)? Is it driven by the increase in entropy?
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