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Does any matter lose electrons or atoms?

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shvcko99:

--- Quote from: Borek on June 01, 2022, 03:02:20 AM ---
--- 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.

--- End quote ---

I understand that Liquids and solids evaporate all the time, no matter what, it is only because of equilibrium that cancel the net effect. But just wondering why does solid evaporate? I cannot remember exactly but as far as I remember forces between atoms/molecules/particles of solid are so strong that's why they are solid, how can the force from the surrounding strong enough to bring them out (even from the surface)??

Borek:
The basic principle is the same for liquids and solids (with plenty on interesting differences): you don't need external force to pull atoms/molecules out. They fluctuate all the time, and energy of each molecule changes all the time around some average value. Sometimes the atom/molecule oscillates/wiggles faster, sometimes slower, sometimes fast enough to jump away.

Enthalpy:
I too had believed that the equilibrium vapour pressure of solids is smaller than liquids, since sublimation takes more energy than evaporation, the difference being the melting heat. BUT data speaks against that.

At the "triple point", vapour is at equilibrium with both the solid and the liquid, which means that the solid and the liquid have the same vapour pressure. More: the vapour pressure varies continuously with the temperature around the melting point. Have a look at the brightly colored "Phase diagram"
  wikipedia
the curve limiting the orange domain of vapour passes smoothly through 0°C.

Which is necessary after all. Ice can be in equilibrium with liquid water, and one can't extract energy from this equilibrium by turbining vapour that would flow from the liquid to the solid, not even temporarily.

Still unclear to me: why the slope of the vapour pressure shows no break at the melting point, since the heat of sublimation exceeds the heat of vaporization.

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