Evaporation requires the removal of heat?

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SUMMARY

The discussion clarifies that evaporation requires heat, specifically latent heat, which is absorbed from the surrounding environment, resulting in a cooling effect. While boiling water adds heat to increase temperature, evaporation can occur at room temperature as energetic molecules escape the liquid. This process leaves the remaining water cooler, as demonstrated by personal experiences like sweating. The explanation provided by user mpv_plate effectively addresses the initial confusion regarding heat and evaporation in cooling towers.

PREREQUISITES
  • Understanding of latent heat and its role in phase changes
  • Basic principles of thermodynamics related to heat transfer
  • Familiarity with the concept of evaporation and its effects on temperature
  • Knowledge of cooling tower operations and their mechanisms
NEXT STEPS
  • Research the principles of latent heat and its applications in cooling systems
  • Explore thermodynamic cycles and their relevance to heat transfer
  • Study the mechanics of evaporation in various environmental conditions
  • Investigate the design and efficiency of cooling towers in industrial applications
USEFUL FOR

Engineers, HVAC professionals, environmental scientists, and anyone interested in thermodynamics and cooling technologies will benefit from this discussion.

dynamicproject
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I'm missing out on something here.

I'm studying how the cooling tower works and it says that the "water evaporates and removes heat". The thing is, shouldn't the heat be added to the water for it to evaporate and thus increasing the heat? If we want water to evaporate, we boil it with fire, which is once again heat addition.

Care to clarify this for me?
 
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Water needs heat to evaporate, but the heat does not increase temperature of water: the heat is used to free the water molecules. It is called the latent heat. Water gets this latent heat from the sorrounding material, so the sorroundings get cooler.
 
We boil it so that the water is hotter than the air and then it evaporates quickly. If we don't boil it then it will be room temperature, and it will still evaporate. This is because water has many molecules in it and some are more energetic than others. The "hotter" (more energetic) molecules and bits of water have enough momentum to escape the liquid and go into the atmosphere. This leaves the liquid cooler because the hot molecules have escaped. This should jive with your personal experience. If we boil water it cools down as it evaporates, the hot water is leaving. If you sweat you cool down because the hot water molecules on your body leave and what is left are colder molecules.
 
Thanks to both of you but the answer I was looking for was answered by mpv_plate. Appreciated!
 

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