Clausius-Clapeyron Calculator
Calculate vapor pressure, temperature, or enthalpy of vaporization using the Clausius-Clapeyron equation.
Clausius-Clapeyron Equation
Solve For:
1 atm
0.001 atm10 atm
atm
373.15 K
200 K600 K
K
= 100.00 °C
358.15 K
200 K600 K
K
= 85.00 °C
40.7 kJ/mol
10 kJ/mol100 kJ/mol
kJ/mol
Final Pressure (P2)
0.577268 atm
P1
1.000000 atm
P2
0.577268 atm
T1
373.15 K (100.00°C)
T2
358.15 K (85.00°C)
Clausius-Clapeyron Equation:
ln(P2/P1) = -(Delta Hvap/R) * (1/T2 - 1/T1)
ln(P2/P1):
-0.549449
Understanding the Clausius-Clapeyron Equation
The Clausius-Clapeyron equation describes how vapor pressure changes with temperature during a phase transition. It is derived from thermodynamic principles and assumes that the enthalpy of vaporization is constant over the temperature range. The equation is essential for predicting boiling points at different pressures and for understanding phase equilibria.
Common Enthalpies of Vaporization
| Substance | Delta Hvap (kJ/mol) | Boiling Point (°C) |
|---|---|---|
| Water | 40.7 | 100 |
| Ethanol | 38.6 | 78.4 |
| Acetone | 30.7 | 56.1 |
| Benzene | 30.8 | 80.1 |
| Ammonia | 23.3 | -33.4 |