1. What is Critical Pressure of Wohl's Real Gas?

Definition: Critical pressure is the minimum pressure required to liquefy a substance at its critical temperature.

Purpose: This calculator determines the critical pressure using Wohl's equation of state, which is important for understanding gas behavior under extreme conditions.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( P_c \) — Critical pressure (Pascal)
• \( [R] \) — Universal gas constant (8.314 J/mol·K)
• \( T_c \) — Critical temperature (Kelvin)
• \( V_c \) — Critical molar volume (m³/mol)

Explanation: The formula relates critical pressure to other critical parameters in Wohl's model of real gas behavior.

3. Importance of Critical Pressure Calculation

Details: Critical pressure is essential for designing high-pressure systems, understanding phase behavior, and in petroleum and chemical engineering applications.

4. Using the Calculator

Tips: Enter the critical temperature in Kelvin and critical molar volume in cubic meters per mole. Both values must be positive.

5. Frequently Asked Questions (FAQ)

Q1: What is the Wohl's equation of state?
A: It's a cubic equation of state used to model real gas behavior, similar to van der Waals but with different parameters.

Q2: What are typical values for critical parameters?
A: Critical temperatures range from 33K (hydrogen) to 1900K (tungsten hexafluoride). Critical volumes are typically 0.0001-0.0005 m³/mol.

Q3: How accurate is this calculation?
A: It provides theoretical values based on Wohl's model. Actual experimental values may differ slightly.

Q4: Can I use this for any gas?
A: Yes, but accuracy varies. It works best for simple, non-polar molecules.

Q5: What units does the calculator use?
A: Temperature in Kelvin, volume in m³/mol, and pressure in Pascals (SI units).