What is Evaporation: Definition and 212 Discussions

Evaporation is a type of vaporization that occurs on the surface of a liquid as it changes into the gas phase. The surrounding gas must not be saturated with the evaporating substance. When the molecules of the liquid collide, they transfer energy to each other based on how they collide with each other. When a molecule near the surface absorbs enough energy to overcome the vapor pressure, it will escape and enter the surrounding air as a gas. When evaporation occurs, the energy removed from the vaporized liquid will reduce the temperature of the liquid, resulting in evaporative cooling.On average, only a fraction of the molecules in a liquid have enough heat energy to escape from the liquid. The evaporation will continue until an equilibrium is reached when the evaporation of the liquid is equal to its condensation. In an enclosed environment, a liquid will evaporate until the surrounding air is saturated.
Evaporation is an essential part of the water cycle. The sun (solar energy) drives evaporation of water from oceans, lakes, moisture in the soil, and other sources of water. In hydrology, evaporation and transpiration (which involves evaporation within plant stomata) are collectively termed evapotranspiration. Evaporation of water occurs when the surface of the liquid is exposed, allowing molecules to escape and form water vapor; this vapor can then rise up and form clouds. With sufficient energy, the liquid will turn into vapor.

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  1. K

    B Question about Hawking Radiation and Iron Stars

    So, I was thinking, the most massive black holes are expected to evaporates in roughly a googol year. Fine. But I was reading that if protons are stable, every planet and non black hole star remains are basically expected to turn into iron star from quantum tunneling after mind numbing time on...
  2. E

    Can detergent also evaporate beside water?

    Hi PhysicsForums, My bed has 4 small plastic footing at each corner, and each footing is soaked in middle of small container of water with detergent (about 4 inches square container) to avoid ants from crawling up the bed in any footing. Can the detergent in the water also evaporate polluting...
  3. D

    I What is the Limiting Mass at the Final Stages of Black Hole Evaporation?

    As Hawking radiation does away with black holes in the eons of time it takes to evaporate, what is the limiting mass at the final stages of the black hole evaporation? Is it Planck mass? or some fractional mass of the initial BH?
  4. jaketodd

    I Hawking's latest contribution, is this an implication?

    Does this mean that everything, including us, will turn into photons/electromagnetic waves some day? Sounds fun! A universe of matter converted entirely to light! I couldn't find any papers yet on this on scholar.google.com Here are some good articles though...
  5. R

    I Atomization and Evaporation: Understanding the Energy Exchange

    Oh, also, I know that it takes a lot of energy to phase change a liquid to a gas, but what if you force the liquid through a small hole that atomizes the liquid. Does the atomized liquid draw the same amount of heat from the surrounding area as its forced to become steam?
  6. C

    Finding how much heat released by evaporation of water

    For this, Dose anybody please know where they got the 120W from? Many thanks!
  7. S

    I Kerr & Nordström Black Hole Evaporation: Q&A

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  8. H

    I Black holes to explode due to evaporation?

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  9. kyphysics

    Science of Evaporation - General & Personal Questions

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  10. dario2

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  11. S

    B What causes the drop of latent heat at lower temperatures in liquid helium?

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  12. Melbourne Guy

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  13. Youssef Ellakany

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  14. Will26040

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  15. Kostik

    B Paradox about black hole evaporation

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  16. Marilyn67

    B Black hole horizon and Hawking evaporation

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  17. StoningTree

    How does humidity affect air cooling?

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  18. B

    Field Evaporation of Contact Charged Spheres: Exploring Possibilities

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  19. Z

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  20. V

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  21. Y

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  22. felipeborges

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  23. F

    B Why does matter always escape while antimatter falls into black holes?

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  24. SpinzTronics

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  25. Z

    I Non-Linear Evaporation: Explained for Beginners

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  26. Guilherme Franco

    How volatile is urea in a water mixture?

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  27. G

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  28. Buzz Bloom

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  29. EEristavi

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  30. J

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  31. A

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  32. V

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  33. H

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  34. C

    Calculate the moisture content of air

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  35. D

    How to avoid boiling/bubbling effect under vacuum?

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  36. S

    I Why do quantum physicists claim that particles can tunnel out of a quantum well?

    Hi everyone,Every time I read an article about black hole evaporation through Hawking radiation, it seems to me that the writer didn't bother to connect all the dots so it will be clear for dummies like me.In many articles, I find 2 contradictory statements:1. Black hole emits a radiation (i.e...
  37. DaveC426913

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  38. neil63

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  39. Adrianus

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  40. Galbi

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  41. S

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  42. Umar Awan

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  43. A

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  44. C

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  45. jmarkwalker

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  46. T

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  47. Alfreds9

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  48. K

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  49. S

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  50. C

    How can I recreate this pressure boiling experiment

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