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Does any matter lose electrons or atoms?

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shvcko99:
I have put down my schoolbag for many years but now I'd like to revise something.

I remember it's said electrons (or molecules? I forget) will lose from surface of liquid because molecular force at those area are weaker

Does this also happen to solid? Or only to liquid because molecular force between particles in solid are much stronger?

Borek:
One process is called evaporation, the other sublimation. Yes, both exist, although evaporation is much faster, and yes, that's because in solids intermolecular forces are stronger.

shvcko99:

--- Quote from: Borek on May 31, 2022, 03:00:57 AM ---One process is called evaporation, the other sublimation. Yes, both exist, although evaporation is much faster, and yes, that's because in solids intermolecular forces are stronger.

--- End quote ---

Does sublimation always exist in solid but just different materials/chemicals have different rate? Is it because of "surrounding" is an open area so that it cannot reach an equilibrium so that there must be always some atoms/molecules/particles escaping from the surface? Is it conceptually correct?

Borek:

--- Quote from: shvcko99 on May 31, 2022, 12:18:40 PM ---Does sublimation always exist in solid but just different materials/chemicals have different rate?
--- End quote ---

Yes & yes.


--- Quote ---Is it because of "surrounding" is an open area so that it cannot reach an equilibrium so that there must be always some atoms/molecules/particles escaping from the surface?
--- End quote ---

Not exactly. Liquids and solids evaporate all the time, no matter what. But at the same time reverse process (condensation/resublimation) occurs. At some point both processes have the same speed so the net effect is zero. To some extent that's the same behavior you describe, just the logic behind is a bit different.

This is best analyzed in terms of phase diagrams and (partial) pressures of the substances involved.

Corribus:
Just to point out also that one thing that differentiates solids from liquids is the rate at which the surface is replenished with pristine material (atoms, molecules, whatever). In a solid, the atomic/molecular arrangement is more or less fixed over realistic timescales, whereas in liquids, surface molecules and non-surface molecules are constantly switching position. Liquid molecules are inherently more mobile, and other forces like convection can play a role in mixing. One effect of this is that surface chemistry plays a more important role in the behavior of solids than liquids - chemistry particularly between the solid material and reactive substances like oxygen in the atmosphere. So, with solids you may form thin overcoatings of oxides and sulfides that have very different properties from the underlying material. So while physical processes like evaporation surely occur in and both solids in liquids, surface chemical transformations (and their effect on the rates of the physical processes) become more complicated and relevant in solids. (Chemistry of course also happens in liquids, but the constant mixing prevents buildup of surface layers. Also reactive substances like oxygen are more readily absorbed into the interior of liquids than the interior of solids.)

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