`T_2 = 1"/"(1/T_1 + ln (P_1/P_2) * (R/H) )`

Enter a value for all fields

The Clausius-Clapeyron Equation for Temperature calculator estimates the temperature where the vapor pressure of a liquid will be a certain value when the vapor pressure at another temperature is known. 

INSTRUCTIONS: Choose units and enter the following:

• (P₁) Vapor Pressure 1
• (ΔH_vap)  Molar Enthalpy of Vaporization
• (T₁)  Temperature 1 (corresponds with P₁)
• (P₂) Temperature 2 

Temperature (T₂): The calculator returns the temperature in degrees Kelvin.  However, the temperature can be automatically converted to compatible units via the pull-down menu. 

The Math

The Clausius-Clapeyron Equation is as follows:

     `ln((P_2)/(P_1)) = (DeltaH_(vap))/R * (1/T_2  - 1/T_1)`  

where R is the ideal gas constant (8.314 J/mol*K)

This calculator solves the above equation for T₂.  Therefore, the Clausius-Clapeyron equation for final pressure is:

   `T_2 = 1"/"(1/T_1 + ln (P_1/P_2) * (R/H) )`

where:

• T₂ = Temperature 2
• H = Molar Enthalpy of Vaporization
• P₂ = Pressure at T₂
• P₁ = Pressure at T₁
• T₁ = Temperature 1
• R = Ideal Gas Constant

Clausius-Clapeyron Equation Calculators

• Clausius-Clapeyron Pressure
• Clausius-Clapeyron Temperature

Supplemental Materials

UCDavis ChemWiki: Clausius-Clapeyron Equation

YouTube: Find the Vapour Pressure (Clausius-Clapeyron Equation)

References

Whitten, et al. "Chemistry" 10th Edition. Pp. 467