1. What is Critical Pressure of Real Gas?

Definition: Critical Pressure of Real Gas is the minimum pressure required to liquify a substance at the critical temperature.

Purpose: This calculator helps determine the critical pressure using the Clausius model of real gas behavior.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( P'c \) — Critical Pressure (Pascals)
• \( [R] \) — Universal gas constant (8.314 J/mol·K)
• \( T'c \) — Critical Temperature (Kelvin)
• \( c \) — Clausius parameter c (empirical parameter)
• \( Vc \) — Critical Volume (m³)

Explanation: The formula relates critical pressure to critical temperature, volume, and an empirical parameter from the Clausius model.

3. Importance of Critical Pressure Calculation

Details: Critical pressure is essential for understanding phase behavior of substances and designing industrial processes involving gases.

4. Using the Calculator

Tips: Enter the critical temperature in Kelvin, Clausius parameter c, and critical volume in cubic meters. All values must be positive.

5. Frequently Asked Questions (FAQ)

Q1: What is the Clausius model?
A: An equation of state for real gases that improves upon the ideal gas law by including empirical parameters.

Q2: How do I find critical temperature and volume?
A: These are typically determined experimentally or found in thermodynamic tables for specific substances.

Q3: What are typical values for Clausius parameter c?
A: This varies by substance but is typically a small positive number (often in the range of 0.0001 to 0.1).

Q4: Why is the universal gas constant used?
A: It provides the necessary proportionality between pressure, volume, and temperature in the equation.

Q5: What are common applications of this calculation?
A: Used in chemical engineering, thermodynamics, and process design involving gases near their critical points.