can someone please explain what it is and how it works
vapor pressure
- Thread starter jd399
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The vapor pressure of a liquid is the equilibrium pressure of a vapor above its liquid (or solid); that is, the pressure of the vapor resulting from evaporation of a liquid (or solid) above a sample of the liquid (or solid) in a closed container.
VP - not affected by surface area
- strong intermolecular bonds means low vp
- high bp means low vp (since the bp is he temperature at which the vp of the liquid equals the environmental pressure surrounding the liquid)
VP - not affected by surface area
- strong intermolecular bonds means low vp
- high bp means low vp (since the bp is he temperature at which the vp of the liquid equals the environmental pressure surrounding the liquid)
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I like thinking of analogies.
Think of it like this. A bunch of molecules in a liquid. When you heat it, more molecules break through the surface of the liquid, kinetic energy collision forces, into the space above. The more molecules that are above the surface, the greater the pressure is above the surface.
So when a molecule has a high bp, more heat is needed to make those molecules break the surface. Thus, there are less molecules above the surface at STP and will have a pretty low BP. ANd vice versa, a low bp needs less heat to make those molecules break into the space above and will have a higher vp.
So BP and VP are inversally proportional.
Also, When you add more solutes to a solution, BP increases. However, bc they are inversaly proprtional, VP decreases.
Hope that made sense and helped a little
