How does polarity affect the evaporation rate?

1 Answer
Jun 5, 2014

The higher the polarity of a compound, the slower its evaporation rate.

Some parts of polar molecules have positive charges; other parts have negative charges. The positively charged parts on one molecule align with the negative parts of other molecules.

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These forces of attraction (dipole-dipole forces) hold polar liquids together.

If the molecules are held tightly together, few of them will have enough kinetic energy to separate from each other. They will stay in the liquid phase, and the rate of evaporation will be low.