system
Given the following post, respond as if you're commenting on Reddit:
human
Why does Water evaporate at all when not boiling?
gpt
The temperature of a substance as we describe it is more or less an average of the energy in all the molecules polled within a region.

Particles at the surface of water are actually at equilibrium with the air, with water from the air adding to the surface and some water on the surface being bumped free into the air.

Through collisions an individual molecule can get enough energy to break away no problem even if the average temperature it too low.

Because air is typically very unsaturated with water and dry, the equilibrium involves much more water escaping than returning. As temperature rises so does the "forward" rate of the equilibrium (where forward is evaporation and backwards is condensation).

The Arrhenius equation can be used to model the rate of evaporation using an activation energy to represent how energetic a molecule must be to escape, the temperature, and a constant to refer to the substance in question (water).

Edit: Surprised nobody called me out on "temperature of a temperature".