Vapor Pressure and Raoult's Law

Flashcards summarizing key concepts of vapor pressure, Raoult's law, and related properties of solutions.

What does Raoult's Law state about vapor pressure of solutions?

The vapor pressure of a solution is the product of the mole fraction of the solvent and the vapor pressure of the pure solvent.

How do you calculate the vapor pressure of a solution containing non-volatile solutes?

Use the formula Psolution = Xsolvent × P_solvent°.

What is vapor pressure lowering (ΔP)?

ΔP is the difference between the vapor pressure of the pure solvent and the vapor pressure of the solution.

What happens to the total vapor pressure of a solution when a volatile solute is present?

The total vapor pressure is the sum of the vapor pressures of the solute and solvent.

What indicates an ideal solution according to Raoult’s law?

In an ideal solution, solute-solvent interactions are similar to solute-solute and solvent-solvent interactions.

What results from stronger solute-solvent interactions in a nonideal solution?

The total vapor pressure of the solution will be less than predicted by Raoult’s law.

How do nonideal solutions deviate from Raoult's Law?

They show either positive or negative deviations based on the strength of solute-solvent interactions compared to solute-solute and solvent-solvent interactions.

What is the formula to find the mole fraction?

Xsolvent = nsolvent / (nsolvent + nsolute).

In an ideal solution, how does the addition of a solute affect the solvent?

The addition of solute dilutes the solvent.

What is the effect of vapor pressure lowering on boiling and freezing points?

It raises the boiling point and lowers the freezing point of the solution compared to the pure solvent.