1. What is the Antoine Equation?

The Antoine equation is a simple 3-parameter fit to experimental vapor pressure data. It relates the vapor pressure of a substance to its temperature and is widely used in chemical engineering and thermodynamics.

2. How Does the Calculator Work?

The calculator uses the Antoine equation:

Where:

• \( P_{sat} \) — Saturation pressure (Pa)
• \( A \) — Antoine constant (dimensionless)
• \( B \) — Antoine constant (K)
• \( C \) — Antoine constant (K)
• \( T \) — Temperature (K)

Explanation: The equation provides a semi-empirical relationship between vapor pressure and temperature for pure components.

3. Importance of Saturation Pressure Calculation

Details: Saturation pressure is crucial for designing distillation columns, predicting phase behavior, and calculating thermodynamic properties of substances.

4. Using the Calculator

Tips: Enter the Antoine constants (A, B, C) for your specific substance and the temperature in Kelvin. The constants are substance-specific and can be found in chemical engineering handbooks.

5. Frequently Asked Questions (FAQ)

Q1: What are typical ranges for Antoine constants?
A: A typically ranges from 10-20, B from 1000-5000 K, and C from -100 to 100 K, but these vary by substance.

Q2: What temperature range is valid for the Antoine equation?
A: The equation is valid only within the temperature range for which the constants were fitted, typically between the triple point and critical point.

Q3: Can this be used for mixtures?
A: No, the Antoine equation is for pure substances only. For mixtures, use Raoult's Law or other mixing rules.

Q4: What are common units for the Antoine equation?
A: The units depend on the form used. This calculator uses the form where P is in Pa and T is in K.

Q5: How accurate is the Antoine equation?
A: It's typically accurate to 1-5% within its valid temperature range, but accuracy depends on the quality of the fitted constants.