Standardized Enthalpies and Entropies
Standardized enthalpies and entropies of some common substances:
| Substance | Entropy - s - | Enthalpy - h - | ||
|---|---|---|---|---|
| Btu/lbmole R | J/gmole K | Btu/lbmole | J/gmole | |
| Acetylene C2H2 | 47.97 | 200.82 | 97,495 | 226,757 |
| Benzene C6H6 | 64.3 | 269.21 | 35,653 | 82,923 |
| n-Butane C4H10 | 74.1 | 310.03 | -53,627 | -124,727 |
| Carbon Dioxide CO2 | 51.03 | 213.66 | -169,183 | -393,492 |
| Carbon Monoxide CO | 47.3 | 197.92 | -47,517 | -110,516 |
| Ethane C2H6 | 54.8 | 229.48 | -36,401 | -84,662 |
| Hydrogen H2 | 31.2 | 130.60 | 0 | 0 |
| Methane CH4 | 44.5 | 186.19 | -32,179 | -74,843 |
| Nitrogen N2 | 45.8 | 191.56 | 0 | 0 |
| Oxygen O2 | 48.99 | 205.09 | 0 | 0 |
| Propane C3H8 | 64.47 | 269.92 | -44,647 | -103,848 |
| Water H2O | 16.72 | 70.00 | -122,976 | -286,022 |
- equilibrium states at 25oC (77oF) and 1 atm
Go to Standard state and Standard enthalpy of formation for listing of standard enthalpy of formation and standard entrypy for more than 370 inorganic substances.
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