How to use the antoine equation vapor pressure calculator
Find the vapour pressure of a liquid at a temperature using the Antoine equation. Defaults are for water. Enter antoine constant a, antoine constant b, antoine constant c, temperature in the fields above; the vapor pressure are computed instantly and plotted on the chart so you can see how the answer changes.
Common searches this calculator answers include “Antoine equation”, “vapour pressure of water”, “Antoine constants”, “calculate antoine equation vapor pressure”, “find vapor pressure”.
Formula
Variables
- A — Antoine constant A (log10 mmHg)
- B — Antoine constant B (K)
- Cc — Antoine constant C (K)
- T — Temperature (°C)
Worked example
With antoine constant a = 8.07131 log10 mmHg, antoine constant b = 1730.63 K, antoine constant c = 233.426 K, temperature = 25 °C, the calculator gives vapor pressure ≈ 23.68641 mmHg; vapor pressure ≈ 3.15792 kPa.
Frequently asked questions
What is the antoine equation vapor pressure calculator used for?
Find the vapour pressure of a liquid at a temperature using the Antoine equation. Defaults are for water. It helps with questions such as “Antoine equation”, “vapour pressure of water”, “Antoine constants”.
What is the formula for the antoine equation vapor pressure calculation?
Vapor pressure (mmHg) = 10^(A-B / (Cc+T)). Vapor pressure (kPa) = [Vapor pressure] × 0.133322. Here A is antoine constant a (log10 mmHg), B is antoine constant b (K), Cc is antoine constant c (K), T is temperature (°C).
What inputs do I need for the antoine equation vapor pressure calculator?
You need antoine constant a in log10 mmHg, antoine constant b in K, antoine constant c in K, temperature in °C. Each field is pre-filled with a typical example so you can see how the result responds as you edit the numbers.
How do I use the antoine equation vapor pressure calculator?
Type values into the input fields. Results and the chart update instantly. Use Reset to restore the example values, Copy results to paste them elsewhere, or Share to copy a link that preserves your inputs.
Is the antoine equation vapor pressure result exact?
Calculations use standard formulas and double-precision arithmetic, then display about seven significant figures. Real-world measurements carry uncertainty, so treat results as estimates unless your inputs are exact.