Evaporation and selection effects
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Calling evaporation “endothermic” is not a harmless technicality; it is a sleight of hand. The contrast with exothermic reactions is the tell. When a reaction is exothermic, stored chemical energy is actually converted into heat in the combined setup; the surroundings warm up. Calling evaporation endothermic suggests the mirror image, as if evaporation reduces the heat of the whole system. It does not. It quietly treats the remaining liquid as the system, then reports the cooling of that subsystem as if heat has been reduced. In a closed system, the heat has not gone away; it has been carried into the vapor as latent heat.
In social science, we call this a selection effect. The molecules that leave the liquid are not a random sample. The highest-energy molecules “select” into the vapor, which mechanically lowers the average energy of the molecules left behind. The apparent cooling is real locally, but the interpretation is wrong if you ignore who has selected out of the frame.