1. What is Raoult's Law?

Raoult's Law states that the vapor pressure of a solution is equal to the mole fraction of the solvent multiplied by the vapor pressure of the pure solvent. It describes the vapor pressure behavior of ideal solutions.

2. How Does the Calculator Work?

The calculator uses Raoult's Law formula:

Where:

• \( P_{sol} \) — Vapor pressure of the solution (Pa)
• \( X_{solvent} \) — Mole fraction of solvent (dimensionless)
• \( P_{pure} \) — Vapor pressure of pure solvent (Pa)

Explanation: The law assumes ideal behavior where the vapor pressure depends only on the concentration of the solvent and its pure vapor pressure.

3. Importance of Vapor Pressure Calculation

Details: Vapor pressure calculations are crucial for understanding colligative properties, predicting boiling points, and designing distillation processes in chemical engineering.

4. Using the Calculator

Tips: Enter mole fraction of solvent (0-1) and pure solvent vapor pressure in Pascals. Both values must be valid positive numbers with mole fraction between 0 and 1.

5. Frequently Asked Questions (FAQ)

Q1: What is an ideal solution?
A: An ideal solution follows Raoult's Law exactly, where intermolecular forces between different molecules are similar to those between identical molecules.

Q2: When does Raoult's Law not apply?
A: Raoult's Law doesn't apply to non-ideal solutions where significant deviations occur due to intermolecular interactions or association/dissociation.

Q3: What are typical vapor pressure units?
A: While Pascals (Pa) are used here, vapor pressure is also commonly measured in mmHg, atm, or bar. 1 atm = 101325 Pa.

Q4: How does temperature affect vapor pressure?
A: Vapor pressure increases with temperature. The pure solvent vapor pressure value should be measured at the same temperature as the solution.

Q5: Can this calculator handle multiple solutes?
A: This calculator assumes a binary solution with one solvent. For multiple solutes, the mole fraction would be calculated differently.