Why do some liquids evaporate faster than others?  

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Evaportion is the change in state of liquid molecules to gas at the surface of a liquid. It occurs at a temperature below the boiling point of the substance. Each molecule that evaporates must have enough energy to overcome the the surface tension or cohesion of molecules at the surface. 

The rate of evaportion depends on several factors, one of which is the nature of the liquid. A liquid with weaker intermolecular attractions will evaporate faster. Intermolecular attractions make liquids more cohesive so that individual molecules must have more energy to escape. Acetone, which is sold as fingernail polish remover, evaporates faster than water. Water has hydrogen bonding, a strong attraction between individual molecules. Because of this water has a higher surface tension and more energy is required for water molecules to escape the liquid phase. Acetone doens't have hydrogen bonding. Its molecules are less attracted to each other.

Evaporation of a liquid occurs faster at higher temperatures, when there's wind, when the surface area of the liquid is larger and when the air above the liquid contains less vapor from the evaporated liquid. The rate of evaporation of water decreases as relative humidity increases. 

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