Evaporation

Real World Example

Imagine trying to pack a suitcase for a trip but only being able to fit a few items at a time. This is similar to evaporation because, just like you can only pack a few items from the top of your messy pile, only the molecules at the surface of a liquid have enough energy to escape and become gas. Just as you carefully select items from the top of your pile to fit into the suitcase, only the surface molecules with sufficient energy leave the liquid, transforming into gas and thus leading to evaporation.