Understanding the Difference Between Evaporation and Boiling

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Evaporation occurs continuously in liquids, such as water, regardless of vapor pressure, allowing molecules to escape from the surface. In contrast, boiling happens when vapor pressure reaches or exceeds atmospheric pressure, enabling molecules to escape not just from the surface but throughout the liquid, forming bubbles. The underlying mechanism for molecular escape is the same in both processes, but the conditions differ, with boiling involving higher vapor pressure that facilitates bulk escape.
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Hello,

This is basic stuff and I feel a bit embarrassed for asking this, but here goes: From what I think I know, evaporation is always happening in a liquid (water, for example) irrespective of the vapor pressure, but boiling only occurs when the vapor pressure is equal or greater than the atmospheric pressure. My question is, how can the molecules escape from the liquid in the former case (evaporation) but are unable to do so in the latter (boiling) until the vapor pressure equals atmospheric pressure?

Thanks!
 
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Molecules escape in both cases and it is exactly the same mechanism. The only difference is that during boiling vapor pressure is so high molecules escape the liquid not only on the surface, but even in the bulk, creating bubbles.
 
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