Nitric acid

• Formula: HNO₃
• Molecular weight: 63.0128
• IUPAC Standard InChI: InChI=1S/HNO3/c2-1(3)4/h(H,2,3,4) Copy

  
• IUPAC Standard InChIKey: GRYLNZFGIOXLOG-UHFFFAOYSA-N Copy
• CAS Registry Number: 7697-37-2
• Chemical structure:
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• Information on this page:
  • Gas phase thermochemistry data
  • Phase change data
  • Henry's Law data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Reaction thermochemistry data
  • Ion clustering data
  • IR Spectrum
  • Vibrational and/or electronic energy levels
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
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Gas phase thermochemistry 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.

Gas Phase Heat Capacity (Shomate Equation)

C_p° = A + B*t + C*t² + D*t³ + E/t²
H° − H°_298.15= A*t + B*t²/2 + C*t³/3 + D*t⁴/4 − E/t + F − H
S° = A*ln(t) + B*t + C*t²/2 + D*t³/3 − E/(2*t²) + G
    C_p = heat capacity (cal/mol*K)
    H° = standard enthalpy (kcal/mol)
    S° = standard entropy (cal/mol*K)
    t = temperature (K) / 1000.

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Phase change 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: William E. Acree, Jr., James S. Chickos

Enthalpy of vaporization

Henry's Law 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: Rolf Sander

Henry's Law constant (water solution)

k_H(T) = k°_H exp(d(ln(k_H))/d(1/T) ((1/T) - 1/(298.15 K)))
k°_H = Henry's law constant for solubility in water at 298.15 K (mol/(kg*bar))
d(ln(k_H))/d(1/T) = Temperature dependence constant (K)

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 evaluated as indicated in comments:
HL - Edward P. Hunter and Sharon G. Lias

Data compiled as indicated in comments:
B - John E. Bartmess
MM - Michael M. Meot-Ner (Mautner)
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron
LL - Sharon G. Lias and Joel F. Liebman

Electron affinity determinations

Proton affinity at 298K

Ionization energy determinations

Appearance energy determinations

De-protonation reactions

 +  =

By formula: NO₃^- + H⁺ = HNO₃

References

Go To: Top, Gas phase thermochemistry data, Phase change data, Henry's Law data, Gas phase ion energetics data, Notes

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

Chase, 1998
Chase, M.W., Jr., NIST-JANAF Themochemical Tables, Fourth Edition, J. Phys. Chem. Ref. Data, Monograph 9, 1998, 1-1951. [all data]

Holeci, 1966
Holeci, I., Chem. Prum., 1966, 16, 5, 267. [all data]

Hunter and Lias, 1998
Hunter, E.P.; Lias, S.G., Evaluated Gas Phase Basicities and Proton Affinities of Molecules: An Update, J. Phys. Chem. Ref. Data, 1998, 27, 3, 413-656, https://doi.org/10.1063/1.556018 . [all data]

Mathur, Rothe, et al., 1976
Mathur, B.P.; Rothe, E.W.; Tang, S.Y.; Mahajan, K.; Reck, G.P., Negative gaseous ions from nitric acid, J. Chem. Phys., 1976, 64, 1247. [all data]

Paulson and Dale, 1982
Paulson, J.F.; Dale, J., Reactions of OH^-.H₂O with NO₂, J. Chem. Phys., 1982, 77, 4006. [all data]

Bernardi, Cacace, et al., 1998
Bernardi, F.; Cacace, F.; de Petris, G.; Pepi, F.; Rossi, I., Gaseous [N2O5]H+, [N2O4]H+, and related species from the addition of NO2+ and NO+ ions to nitric acid and its derivatives, J. Phys. Chem. A, 1998, 102, 1987. [all data]

Lloyd, Roberts, et al., 1975
Lloyd, D.R.; Roberts, P.J.; Hillier, I.H., Electronic structure of nitric acid studied by photoelectron spectroscopy and molecular orbital calculation, J. Chem. Soc. Faraday Trans. 2, 1975, 71, 496. [all data]

Frost, Lee, et al., 1975
Frost, D.C.; Lee, S.T.; McDowell, C.A.; Westwood, N.P.C., Photoelectron spectroscopic studies of some nitrosyl and nitryl halides nitric acid, J. Electron Spectrosc. Relat. Phenom., 1975, 7, 331. [all data]

Nicholson, 1965
Nicholson, A.J.C., Photoionization-efficiency curves. II. False and genuine structure, J. Chem. Phys., 1965, 43, 1171. [all data]

Ames and Turner, 1976
Ames, D.L.; Turner, D.W., Photoelectron spectroscopic studies of dinitrogen tetroxide and dinitrogen pentoxide, Proc. R. Soc. London A:, 1976, 348, 175. [all data]

Jochims, Denzer, et al., 1992
Jochims, H.-W.; Denzer, W.; Baumgartel, H.; Losking, O.; Willner, H., Photochemical decay reactions of N₂O₅, HNO₃, ClNO₃ and BrNO₃ in the energy range 10-20 eV, Ber. Bunsen-Ges. Phys. Chem., 1992, 96, 573. [all data]

Davidson, Fehsenfeld, et al., 1977
Davidson, J.A.; Fehsenfeld, F.C.; Howard, C.J., The heats of formation of NO₃- and NO₃- association complexes with HNO₃ and HBr, Int. J. Chem. Kinet., 1977, 9, 17. [all data]

Refaey and Franklin, 1976
Refaey, K.M.A.; Franklin, J.L., Endoergic ion-molecule-collision processes of negative ions. V. Collision of I- on HNO₃. The electron affinity of NO₃, J. Chem. Phys., 1976, 64, 4810. [all data]

Ferguson, Dunkin, et al., 1972
Ferguson, E.E.; Dunkin, D.B.; Fehsenfeld, F.C., Reactions of NO₂^- and NO₃^- with HCl and HBr, J. Chem. Phys., 1972, 57, 1459. [all data]

Berkowitz, Chupka, et al., 1971
Berkowitz, J.; Chupka, W.A.; Gutman, D., Electron Affinities of O₂, O₃, NO, NO₂, and NO₃ by Endothermic Charge Transfer, J. Chem. Phys., 1971, 55, 6, 2733, https://doi.org/10.1063/1.1676488 . [all data]

Notes

Go To: Top, Gas phase thermochemistry data, Phase change data, Henry's Law data, Gas phase ion energetics data, References

• Symbols used in this document:
  

  AE	Appearance energy
  EA	Electron affinity
  S°gas,1 bar	Entropy of gas at standard conditions (1 bar)
  d(ln(kH))/d(1/T)	Temperature dependence parameter for Henry's Law constant
  k°H	Henry's Law constant at 298.15K
  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔvapH	Enthalpy of vaporization

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