Consider a vessel with a volatile liquid in it. Now a non-volatile solute is added to it. The reason that I have come across says that less surface area is available for evaporation and hence this effect. But this does not make sense to me as we can have liquid in container of all shapes and sizes and will still get the same Vapor Pressure.
Some users have suggested me a link to a similar question. The answers in the link are remarkable but the explanation I was hoping for was more likely to involve forces as in Physics and maybe a sort of "free body diagram" explaining how these forces are acting words rather than actual diagram will be fine too rather than thermodynamic picture. Higher temperature means higher kinetic energy and less collisions needed for the same pressure.
Some molecules of the solvent in the chamber's "atmosphere" will dissolve into the open beaker of solvent, and that process continues until all the solute evaporates. Since the solute dissolves into the solvent, it is absorbed from the atmosphere, lowering the pressure.
If we add non volatile solute to solvent for example water, we decrease the tendency of water to evaporate in gas phase because solute particle obstructs the evaporation of water in gas phase therefore vapour pressure decrease when we add non volatile solute to solvent like water.
This image is from ncert:. Sign up to join this community. The best answers are voted up and rise to the top. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Vapor pressure is a measurement of the likelihood of the molecules of a pure solvent to change from the liquid to the vapor phase. Compare two solvents, water and alcohol.
Of these two solvents, alcohol has a greater tendency to have its molecules at the liquid surface escape into the gas phase. We call this evaporation. As a result, the vapor pressure for alcohol is greater than that of water for a given temperature. If you add a nonvolatile solute to solvent such as water, you decrease the tendency for water molecules to evaporate into the gas phase.
In essence, the solute particles obstruct or reduce the likelihood of evaporation. As a result, fewer molecules change from the liquid to the gas phase, thus reducing the vapor pressure. How do you calculate freezing point depression?
How can freezing point depression determine purity? How does the nature of the solute affect boiling point? How do colligative properties affect freezing point? What colligative property causes ice to melt? Why do colligative properties depend on the number of particles?
How do ionic solutes affect the boiling point? How does solubility affect boiling point?
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