Why do all liquids evaporate at different rates?

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Evaporation is a physical change in which a substance changes from the liquid state to the gas phase. This is typically seen when heat is added to a liquid. This increases the kinetic energy of the molecules and they are able to escape the attractive forces of other similar molecules and enter the gas phase.

A number of factors affect the evaporation of a liquid. The boiling point is one of them. Water boils at 100 degrees Celsius; other liquids have different boiling points. Pressure is also a significant factor. At higher altitudes, a drop in pressure means that the boiling point of water decreases. The density and surface tension of the liquid also affect its rate of evaporation. Liquids with higher densities and higher surface tensions have lower rates of evaporation.

This means that there are a number of factors which may affect the evaporation rate of liquids and since these factors may vary from liquid to liquid, different liquids have different rates of evaporation.

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