Standard Enthalpies of Formation of Inorganic Compounds

Standard Enthalpies of Formation of selected Inorganic Compounds
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Standard Enthalpies of Formation of Inorganic Compounds

 

The standard enthalpy of formation ΔΗ°f of a substance is the change in enthalpy for the reaction that forms 1 mol of the substance from its elements with all reactants and products at 1 atm pressure and usually 298.15 K. For any element in its most stable state at 298 K and 1 atm pressure, ΔΗ°f = 0.

A bond dissociation enthalpies table can be found in the post "Bond Dissociation Enthalpies".

 

Table 1: Standard Molar Enthalpies of Formation ΔΗ°f at 25 °C (298.15K)
Substance Formula ΔΗ°f 
Calcium carbonate CaCO3(s) -1207.1
Calcium oxide CaO(s) -635.5
Carbon dioxide CO2(g) -393.5
Carbon monoxide CO(g) -110.5
Hydrogen bromide HBr(g) -36.23
Hydrogen chloride HCl(g) -92.30
Hydrogen fluoride HF(g) -268.6
Hydrogen iodide HI(g) 25.9
Magnesium carbonate MgCO3(s) -1111.69 
Nitrogen oxide NO(g) 90.29
Nitrogen dioxide NO2(g) 33.10
Nitric acid HNO3(g) -134.31
Sulfur dioxide SO2(g) -296.81
Sulfur trioxide SO3(g) -395.77 
Sulfuric acid H2SO4(l) -811.30
Silver chloride AgCl(s) -127.0
Sodium bicarbonate NaHCO3(s) -947.7
Sodium carbonate NaCO3(s) -1130.9
Sodium chloride NaCl(s) -410.9
Water H2O (l) -285.8
Water vapor H2O (g) -241.8

 

References

  1. CRC Handbook of Chemistry and Physics, 52nd edition, The Chemical Rubber Co., (1971)
  2. David W. Oxtoby, H.P. Gillis, Alan Campion, “Principles of Modern Chemistry”, Sixth Edition, Thomson Brooks/Cole, 2008
  3. Steven S. Zumdahl, “Chemical Principles”  6th Edition, Houghton Mifflin Company, 2009

Key Terms

standard enthalpies of formation, molar enthalpies of formation, table of standard enthalpies of formation ,

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