Vapour Pressure Calculator Using Clausius-Clapeyron Equation

Vapour Pressure Calculator

Calculate the vapour pressure using the Clausius-Clapeyron equation: $$ P = P_0 \exp\!\left[-\frac{\Delta H_{vap}}{R}\left(\frac{1}{T} – \frac{1}{T_0}\right)\right] $$

* Enter the reference vapour pressure $P_0$ (Pa) at $T_0$ (K), the latent heat of vaporization $\Delta H_{vap}$ (J/mol), and the desired temperature $T$ (K).

Step 1: Enter Parameters

Reference Vapour Pressure, $ P_0 $ (Pa):

e.g., 101325 Pa (atmospheric pressure)

Reference Temperature, $ T_0 $ (K):

e.g., 373.15 K (boiling point of water)

Latent Heat of Vaporization, $ \Delta H_{vap} $ (J/mol):

e.g., 40650 J/mol (example value; adjust as needed)

Desired Temperature, $ T $ (K):

e.g., 298.15 K (25°C)

Step 1: Enter Parameters

Calculated Vapour Pressure