Phosphoric Acid

• Formula: H₃O₄P
• Molecular weight: 97.9952
• IUPAC Standard InChI: InChI=1S/H3O4P/c1-5(2,3)4/h(H3,1,2,3,4) Copy

  
• IUPAC Standard InChIKey: NBIIXXVUZAFLBC-UHFFFAOYSA-N Copy
• CAS Registry Number: 7664-38-2
• Chemical structure:
  This structure is also available as a 2d Mol file or as a computed 3d SD file
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• Other names: Orthophosphoric acid; Phosphoric acid ortho; o-Phosphoric acid; Acide phosphorique; Acido fosforico; EVITs; Fosforzuuroplossingen; Phosphorsaeureloesungen; Sonac; UN 1805; H3PO4; Marphos; NFB; White phosphoric acid
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• Information on this page:
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Condensed phase thermochemistry data
  • Reaction thermochemistry data
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Gas phase ion energetics data

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled by: John E. Bartmess

De-protonation reactions

H₂O₄P^- +  =

By formula: H₂O₄P^- + H⁺ = H₃O₄P

References

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Morris, Knighton, et al., 1997
Morris, R.A.; Knighton, W.B.; Viggiano, A.A.; Hoffman, B.C.; Schaeffer III, H.F., The Gas-phase Acidity of H3PO4, J. Chem. Phys., 1997, 106, 9, 3545, https://doi.org/10.1063/1.473465 . [all data]

Notes

Go To: Top, Gas phase ion energetics data, References

• Symbols used in this document:
  

  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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