Table of Some Standard Enthalpies of Formation at 25°C
| Compound | ΔHf/kJ
mol–1 | ΔHf/kcal
mol–1 | Compound | ΔHf/kJ
mol–1 | ΔHf/kcal
mol–1 |
| AgCl(s) | –127.068
| –30.35
| H2O(g) | –241.818
| –57.79
|
| AgN3(s) | +620.6
| +148.3
| H2O(l) | –285.8
| –68.3
|
| Ag2O(s) | –31.0
| –7.41
| H2O2(l) | –187.78
| –44.86
|
| Al2O3(s) | –1675.7
| –400.40
| H2S(g) | –20.63
| –4.93
|
| Br2(l) | 0.0
| 0.00
| HgO(s) | –90.83
| –21.70
|
| Br2(g) | +30.907
| +7.385
| I2(s) | 0.0
| 0.0
|
| C(s), graphite | 0.0
| 0.00
| I2(g) | +62.438
| +14.92
|
| C(s), diamond | +1.895
| +0.453
| KCl(s) | –436.747
| –104.36
|
| CH4(g) | –74.81
| –17.88
| KBr(s) | –393.798
| –94.097
|
| CO(g) | –110.525
| –26.41
| MgO(s) | –601.7
| –143.77
|
| CO2(g) | –393.509
| –94.05
| NH3(g) | –46.11
| –11.02
|
| C2H2(g) | +226.73
| +54.18
| NO(g) | +90.25
| +21.57
|
| C2H4(g) | +52.26
| +12.49
| NO2(g) | +33.18
| +7.93
|
| C2H6(g) | –84.68
| –20.23
| N2O4(g) | +9.16
| +2.19
|
| C6H6(l) | +49.03
| +11.72
| NF3(g) | –124.7
| –29.80
|
| CaO(s) | –635.09
| –151.75
| NaBr(s) | –361.062
| –86.28
|
| CaCO3(s) | –1206.92
| –288.39
| NaCl(s) | –411.153
| –98.24
|
| CuO(s) | –157.3
| –37.59
| O3(g) | +142.7
| +34.11
|
| Fe2O3(s) | –824.2
| –196.9
| SO2(g) | –296.83
| –70.93
|
| HBr(g) | –36.4
| –8.70
| SO3(g) | –395.72
| –94.56
|
| HCl(g) | –92.307
| –22.06
| ZnO(s) | –348.28
| –83.22
|
| HI(g) | +26.48
| +6.33
|
Above is a table of standard enthalpies of formation at 25°C. This is the enthalpyA thermodynamic state function, symbol H, that equals internal energy plus pressure x volume; the change in enthalpy corresponds to the energy transferred as a result of a temperature difference (heat transfer) when a reaction occurs at constant pressure. change which occurs when a compound is formed from its constituent elements. For instance, the enthalpy of formationThe enthalpy change that occurs during the formation of a compound from its component elements in their most stable forms. See also standard enthalpy of formation. value of ΔHm = –285.8 kJ mol–1 is the enthalpy change for the reaction: H2(g) + ½O2(g) → H2O(l). It is important to note that the enthalpy of formation for an element in its most stable state is 0. Using these enthalpies of formation and Hess' Law the enthalpy change of any reaction involving the compounds with a known enthalpy of formation can be determined.
This table is found on CoreChem:Standard Enthalpies of Formation
Printer-friendly version
PDF versionOur Partners:
Our Sponsors:
Find us:
- © Chemical Education Digital Library
- Contact
- Privacy
- Terms of Use
Diigolet
Add to Diigo!Term of the Day
An estimate of the size of an ionAn atom or covalently bonded set of atoms that carries an overall net charge. in an ionic compoundA compound containing oppositely charged ions held together by electrostatic attraction. Usually the ions are in a crystal lattice with positive ions surrounded by negative ions and negative ions surrounded by positive ions.; found from the internuclear distanceThe distance between the nuclei of nearest-neighbor atoms or ions in an element or compound. Bond distances and ionic radii are calculated from this quantity because atoms have no discrete edges. between ions in a crystal latticeAn orderly, repeating arrangement of points in 3-D space in which each p;oint has surroundings identical to every other point. A crystal's constituent atoms, molecules, and ions are arranged about each lattice point..
Search Glossary
User login
Print Options
- Printer Friendly Version will open a new window that has a clean view of the page you are viewing, plus any sub-pages. Warning: if you attempt to view a print version of the top page of a path, this could result in a very large file.
- PDF Version will prompt a download of only the current page you are viewing.