1. What is Critical Pressure using Wohl Equation?

Definition: This calculator determines the critical pressure of a real gas using the Wohl equation, given the Wohl parameter a, critical temperature, and critical molar volume.

Purpose: It helps in thermodynamic calculations and understanding the behavior of real gases at critical conditions.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( P_c \) — Critical Pressure (Pascal)
• \( a \) — Wohl parameter a
• \( T_c \) — Critical Temperature (Kelvin)
• \( V_c \) — Critical Molar Volume (m³/mol)

Explanation: The Wohl parameter a is divided by six times the critical temperature multiplied by the square of the critical molar volume.

3. Importance of Critical Pressure Calculation

Details: Critical pressure is essential for understanding phase behavior, designing chemical processes, and predicting gas properties under extreme conditions.

4. Using the Calculator

Tips: Enter the Wohl parameter a, critical temperature in Kelvin, and critical molar volume in m³/mol. All values must be positive.

5. Frequently Asked Questions (FAQ)

Q1: What is the Wohl equation?
A: The Wohl equation is a cubic equation of state used to describe the behavior of real gases.

Q2: What are typical values for Wohl parameter a?
A: The Wohl parameter a is substance-specific and typically ranges from 100 to 1000 Pa·m⁶/mol² for common gases.

Q3: How accurate is this calculation?
A: The calculation provides an estimate based on the Wohl equation. For precise work, experimental data should be used.

Q4: What units should I use?
A: Use consistent SI units - Pascals for pressure, Kelvin for temperature, and m³/mol for volume.

Q5: Can I use this for any gas?
A: This calculation works for gases that can be reasonably described by the Wohl equation, but accuracy varies by substance.