Clausius-Clapeyron Calculator

Vapor pressure at a new temperature

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Clausius-Clapeyron

Vapor pressure at a new temperature

$$\ln\!\frac{P_2}{P_1}=-\frac{\Delta H_{vap}}{R}\!\left(\frac{1}{T_2}-\frac{1}{T_1}\right)$$

T in Kelvin; pressure units cancel. Assumes constant $\Delta H_{vap}$ and ideal vapor.

P₁ (any unit)

T₁ (K)

ΔH_vap (J/mol)

T₂ (K)

All fields required; T₁ and T₂ nonzero.

Vapor Pressure P₂

—same units as P₁

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