1. What is Pressure of Real Gas using Wohl Equation?

Definition: This calculator computes the pressure of a real gas using the Wohl equation of state, which accounts for non-ideal behavior.

Purpose: It helps chemists and engineers determine gas pressure more accurately than the ideal gas law for real-world conditions.

2. How Does the Calculator Work?

The calculator uses the Wohl equation:

Where:

• \( P \) — Pressure of gas (Pascals)
• \( R \) — Universal gas constant (8.314 J/mol·K)
• \( T \) — Temperature (Kelvin)
• \( V_m \) — Molar volume (m³/mol)
• \( a, b, c \) — Wohl parameters specific to each gas

Explanation: The equation accounts for molecular size (b), intermolecular forces (a), and higher-order corrections (c).

3. Importance of Wohl Equation

Details: Provides more accurate pressure calculations than ideal gas law for real gases, especially at high pressures and low temperatures.

4. Using the Calculator

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

5. Frequently Asked Questions (FAQ)

Q1: What are typical values for Wohl parameters?
A: Parameters vary by gas. For example, for CO₂: a ≈ 3.6, b ≈ 0.0427, c ≈ 2300 (units depend on parameterization).

Q2: When should I use Wohl equation instead of ideal gas law?
A: When dealing with high pressures (>10 atm) or low temperatures near condensation point.

Q3: How do I find Wohl parameters for a specific gas?
A: Consult thermodynamic tables or fit parameters to experimental PVT data.

Q4: What's the difference between Wohl and van der Waals equations?
A: Wohl equation includes an additional term (c) for better accuracy with polar gases.

Q5: What units should I use for molar volume?
A: Molar volume must be in cubic meters per mole (m³/mol) for this calculator.