Re:In a surprising finding, light can make water evaporate w...
by fspeech on Thursday November 02, 2023 @04:14PM
(#38119431)
Entropy favors the vapor form. It doesn't necessarily take energy to evaporate.
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Re:In a surprising finding, light can make water evaporate w...
by frud on Thursday November 02, 2023 @04:55PM
(#38120011)
It takes [40.66 kJ/mol](https://en.wikipedia.org/wiki/Enthalpy_of_vaporization) to vaporize water. There are no shortcuts.
Re:In a surprising finding, light can make water evaporate w...
by stubish on Thursday November 02, 2023 @07:41PM
(#38121998)
The shortcut is apparently breaking the bonds of groups of molecules, rather than supplying enough energy to break all the bonds of each individual molecule. But still technically correct, with the airborne groups breaking apart into individual modules cooling the air. But you don't have to supply all that energy and get to break some theoretical limits.
Re:In a surprising finding, light can make water evaporate w...
by pdonis on Thursday November 02, 2023 @04:55PM
(#38120016)
> Entropy favors the vapor form.
Under the conditions of these experiments (and under most ordinary conditions on Earth), yes. However:
> It doesn't necessarily take energy to evaporate.
Yes, it does. The water molecules in liquid water are bound to each other; that binding energy has to be supplied to enable evaporation. It just doesn't have to be "thermal" energy.
It would be correct to say that it doesn't necessarily take externally applied energy for water to evaporate. Water can evaporate using just its own internal thermal energy. In this case the evaporation process will cause the water to cool.