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Gas Compressibility Factor Formula

Compressibility Factor Equation:

\[ Z = \frac{P V}{n R T} \]

Pa
mol
K

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1. What is the Compressibility Factor?

The compressibility factor (Z) is a dimensionless quantity that describes the deviation of real gas behavior from ideal gas behavior. It compares the actual volume of a gas to the volume predicted by the ideal gas law under the same conditions.

2. How Does the Calculator Work?

The calculator uses the compressibility factor equation:

\[ Z = \frac{P V}{n R T} \]

Where:

Explanation: For an ideal gas, Z = 1. When Z < 1, attractive forces dominate; when Z > 1, repulsive forces dominate.

3. Importance of Compressibility Factor

Details: The compressibility factor is crucial in chemical engineering, thermodynamics, and gas processing for accurate prediction of gas behavior under various pressure and temperature conditions.

4. Using the Calculator

Tips: Enter pressure in Pascals, volume in cubic meters, number of moles, and temperature in Kelvin. All values must be positive and non-zero.

5. Frequently Asked Questions (FAQ)

Q1: What does Z = 1 mean?
A: Z = 1 indicates ideal gas behavior, where the gas follows the ideal gas law exactly.

Q2: When is Z typically less than 1?
A: Z < 1 usually occurs at low temperatures and moderate pressures where intermolecular attractive forces reduce the volume.

Q3: When is Z typically greater than 1?
A: Z > 1 occurs at high pressures where the finite size of gas molecules becomes significant, increasing the volume.

Q4: What is the range of Z values?
A: Z can range from near 0 (for highly compressed gases) to values greater than 2 for some gases at very high pressures.

Q5: How does Z vary with temperature and pressure?
A: Z generally approaches 1 as temperature increases and pressure decreases. At the Boyle temperature, Z = 1 over a range of pressures.

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