Why the fuck does water evaporate

cmon somebodys gotta know

Molecules vibrate more the hotter they get, so when liquid water is heated to a certain point, the molecules vibrate so strongly that they break the bonds that hold each other together. Without these bonds, the molecules float freely into the air as vapor.

Because that's the entropically favorable thing to do.

Molecules from the air collide with molecules on the surface of a body of water. Often these collisions do not generate enough energy to break the bonds of surface tension, but occasionally they do, chipping molecules of water away into the air creating vapor. Enough of those collisions will cause the water to evaporate entirely. This is why windy environments cause water to evaporate more quickly, as do hot environments where the kinetic energy of air molecules is greater.

Think of water ( or any volatile liquid) as a pool of atoms that are constantly jumping up and trying to escape whenever they have enough energy to do so. You can an equilibrium between these high energy atoms and low energy atoms that sit down, the higher temperature of these atoms, the more the equilibrium shifts to favor the atoms jumping and you see water molecules become vapor molecules. I probably butchered this but I tried to convey the way it was taught to me, of course I'm not stupid enough to warrant this oversimplification anymore but I always found thinking about it on an atomic level to ease my understanding of a concept

because magic

aliens

Water molecules are attracted to one another because each water molecule has its charge distributed unevenly (oxygen attracts more negative charge than the two hydrogens) The water molecules are drawn to one another from the attractive forces that arise from the charges. When the water molecules have a high enough temperature, they have a high enough energy to overcome the forces drawing them together and hence move freely as a gas. This doesn't take into account interactions with the atmosphere the water may be in, because I don't know enough about the subject to comment on that part.

>>8323222
I understand why water boils when heated to 100C
but water evaporates at room temp. Why?

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109KB, 500x748px

>>8323194

>I can't use google: the post

Intermolecular forces (hydrogen bonding in water) cause cohesive attraction between discrete molecules in liquids - and at any given temperature under the critical point, some fractional magnitude of water molecules in an aqueous solution will possess enough kinetic energy to escape the intermolecular forces present and enter the vapour phase. The transition from liquid to vapour (evaporation) always occurs at the interface between the liquid and air phase for 'ordinary' evaporation.

>>8323194
it's because the rate of water molecules leaving the liquid puddle is larger than the rate of water molecules entering it. It's called equilibrium being out of balance.

>>8324851
>What are partial pressures?

>>8324851
Because temperature is a distribution of molecular energies. Not every molecule has the same energy, and the ones on the high end of the distribution escape into the air where they can be blown away. This lowers the temperature of the puddle and allows more heat to be transferred from the environment. This gives more molecules the higher energy they need to escape the puddle. This process repeats until the puddle is evaporated.

t. talking out of my ass

its simple - energy and entropy are balanced but energy is constant at all temps whereas entropy 'wins out' when you increase temp as entropy depends on temp

Because it has a vapor pressure. It's a driving force that makes a liquid evaporate below it's boiling point. In an enclosed system, the water would EVENTUALLY stop evaporating once the partial pressure of water equals it's vapor pressure.