1. What is Osmotic Pressure given Vapour Pressure?

Definition: This calculator determines the osmotic pressure of a solution based on the difference between the vapour pressure of the pure solvent and the solution.

Purpose: It helps chemists and researchers understand solution properties and predict solvent behavior across semipermeable membranes.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( \pi \) — Osmotic pressure (Pascal)
• \( p_o \) — Vapour pressure of pure solvent (Pa)
• \( p \) — Vapour pressure of solvent in solution (Pa)
• \( [R] \) — Universal gas constant (8.314 J/mol·K)
• \( T \) — Temperature (Kelvin)
• \( V_m \) — Molar volume (m³/mol)

Explanation: The formula relates the vapour pressure lowering to the osmotic pressure through thermodynamic principles.

3. Importance of Osmotic Pressure Calculation

Details: Osmotic pressure is crucial for understanding biological systems, designing separation processes, and developing pharmaceutical formulations.

4. Using the Calculator

Tips: Enter the vapour pressures in Pascals, temperature in Kelvin, and molar volume in m³/mol. All values must be positive.

5. Frequently Asked Questions (FAQ)

Q1: What is the physical meaning of osmotic pressure?
A: It's the minimum pressure needed to prevent solvent flow through a semipermeable membrane due to concentration differences.

Q2: How does temperature affect osmotic pressure?
A: Osmotic pressure increases with temperature, as shown by the direct proportionality in the formula.

Q3: What are typical values for molar volume?
A: For water at STP, it's about 18×10⁻⁶ m³/mol (18 mL/mol).

Q4: Can this calculator be used for non-ideal solutions?
A: The formula assumes ideal behavior. For non-ideal solutions, activity coefficients should be considered.

Q5: How accurate is this calculation?
A: It provides theoretical values accurate for dilute, ideal solutions. Real systems may show deviations.