|MadSci Network: Chemistry|
Usually a salt added to water will decrease the evaporation rate of the water. This is due to the lowering of the vapor pressure of a solvent (water in this case) by a solute (salt in this case). This is called a colligative property. In the context of this question, this is a property that depends on the number of particles of the solute dissolved in the solvent. The basic laws (Henery's Law, Raoult's Law)apply to non-ionic materials. These laws are discussed in freshman level chemistry texts. Things get more complicated when ionic salts, such as NaCl, are considered. Your Science/Chemistry teacher may have some references that are useful to you.
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