Nitric acid

• Formula: HNO₃
• Molecular weight: 63.0128
• IUPAC Standard InChI:
  

  InChI=1S/HNO3/c2-1(3)4/h(H,2,3,4) Download the identifier in a file.

• IUPAC Standard InChIKey: GRYLNZFGIOXLOG-UHFFFAOYSA-N
• CAS Registry Number: 7697-37-2
• Chemical structure:
  This structure is also available as a 2d Mol file or as a computed 3d SD file
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• Information on this page:
  • Ion clustering data
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Phase change data
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  • Henry's Law data
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Ion clustering 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 as indicated in comments:
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
B - John E. Bartmess

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. Searches may be limited to ion clustering reactions. A general reaction search form is also available.

Clustering reactions

 +  = (  )

By formula: Br^- + HNO₃ = (Br^-  HNO₃)

Quantity	Value	Units	Method	Reference	Comment
rH°	20.0	kcal/mol	FA	Davidson, Fehsenfeld, et al., 1977	gas phase; From thermochemical cycle,switching reaction(Br-/NO3-HNO3/HBr), «DELTA»rH>; M
Quantity	Value	Units	Method	Reference	Comment
rS°	18.5	cal/mol*K	FA	Davidson, Fehsenfeld, et al., 1977	gas phase; From thermochemical cycle,switching reaction(Br-/NO3-HNO3/HBr), «DELTA»rH>; M

Free energy of reaction

rG° (kcal/mol)	T (K)	Method	Reference	Comment
13.4	367.	FA	Davidson, Fehsenfeld, et al., 1977	gas phase; From thermochemical cycle,switching reaction(Br-/NO3-HNO3/HBr), «DELTA»rH>; M

(  ) +  = (  2)

By formula: (Br^-  HNO₃) + HNO₃ = (Br^-  2HNO₃)

Quantity	Value	Units	Method	Reference	Comment
rH°	18.1	kcal/mol	FA	Davidson, Fehsenfeld, et al., 1977	gas phase; From thermochemical cycle(Br-/NO3- - HNO3/HBr), Entropy change calculated or estimated; M
Quantity	Value	Units	Method	Reference	Comment
rS°	23.6	cal/mol*K	N/A	Davidson, Fehsenfeld, et al., 1977	gas phase; From thermochemical cycle(Br-/NO3- - HNO3/HBr), Entropy change calculated or estimated; M
Quantity	Value	Units	Method	Reference	Comment
rG°	11.1	kcal/mol	FA	Davidson, Fehsenfeld, et al., 1977	gas phase; From thermochemical cycle(Br-/NO3- - HNO3/HBr), Entropy change calculated or estimated; M

(HO₄S^-  ) +  = (HO₄S^-  2)

By formula: (HO₄S^-  HNO₃) + HNO₃ = (HO₄S^-  2HNO₃)

Quantity	Value	Units	Method	Reference	Comment
rH°	18.4	kcal/mol	ATM	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M
Quantity	Value	Units	Method	Reference	Comment
rS°	25.	cal/mol*K	N/A	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M

Free energy of reaction

rG° (kcal/mol)	T (K)	Method	Reference	Comment
12.6	233.	ATM	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M

(HO₄S^-  2) +  = (HO₄S^-    2)

By formula: (HO₄S^-  2H₂O₄S) + HNO₃ = (HO₄S^-  HNO₃  2H₂O₄S)

Quantity	Value	Units	Method	Reference	Comment
rH°	15.9	kcal/mol	ATM	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M
Quantity	Value	Units	Method	Reference	Comment
rS°	25.	cal/mol*K	N/A	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M

Free energy of reaction

rG° (kcal/mol)	T (K)	Method	Reference	Comment
10.3	233.	ATM	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M

(HO₄S^-  3) +  = (HO₄S^-    3)

By formula: (HO₄S^-  3H₂O₄S) + HNO₃ = (HO₄S^-  HNO₃  3H₂O₄S)

Quantity	Value	Units	Method	Reference	Comment
rH°	16.9	kcal/mol	ATM	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M
Quantity	Value	Units	Method	Reference	Comment
rS°	25.	cal/mol*K	N/A	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M

Free energy of reaction

rG° (kcal/mol)	T (K)	Method	Reference	Comment
11.1	233.	ATM	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M

(  ) +  = (    )

By formula: (NO₃^-  HBr) + HNO₃ = (NO₃^-  HNO₃  HBr)

Quantity	Value	Units	Method	Reference	Comment
rH°	16.0 ± 2.0	kcal/mol	TDEq	Davidson, Fehsenfeld, et al., 1977	gas phase; B
Quantity	Value	Units	Method	Reference	Comment
rG°	9.6 ± 2.8	kcal/mol	TDEq	Davidson, Fehsenfeld, et al., 1977	gas phase; B

 +  = (  )

By formula: NO₃^- + HNO₃ = (NO₃^-  HNO₃)

Quantity	Value	Units	Method	Reference	Comment
rS°	24.	cal/mol*K	N/A	Davidson, Fehsenfeld, et al., 1977	gas phase; Entropy change calculated or estimated, DG>, «DELTA»rH>; M

(  ) +  = (  2)

By formula: (NO₃^-  HNO₃) + HNO₃ = (NO₃^-  2HNO₃)

Quantity	Value	Units	Method	Reference	Comment
rH°	18.3 ± 1.0	kcal/mol	TDAs	Davidson, Fehsenfeld, et al., 1977	gas phase; B,M
rH°	16.00 ± 0.80	kcal/mol	TDAs	Wlodek, Luczynski, et al., 1980	gas phase; B,M
rH°	18.4	kcal/mol	ATM	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M
rH°	17.7	kcal/mol	HPMS	Lee, Keesee, et al., 1980	gas phase; M
rH°	20.0	kcal/mol	ATM	Arnold and Qiu, 1984	gas phase; Entropy change calculated or estimated; M
Quantity	Value	Units	Method	Reference	Comment
rS°	25.	cal/mol*K	N/A	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M
rS°	22.1	cal/mol*K	FA	Davidson, Fehsenfeld, et al., 1977	gas phase; M
rS°	25.	cal/mol*K	N/A	Arnold and Qiu, 1984	gas phase; Entropy change calculated or estimated; M
rS°	23.1	cal/mol*K	HPMS	Wlodek, Luczynski, et al., 1980	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
rG°	11.7 ± 2.2	kcal/mol	TDAs	Davidson, Fehsenfeld, et al., 1977	gas phase; B,M
rG°	9.00 ± 0.30	kcal/mol	TDAs	Wlodek, Luczynski, et al., 1980	gas phase; B

Free energy of reaction

rG° (kcal/mol)	T (K)	Method	Reference	Comment
12.6	233.	ATM	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M
13.8	250.	ATM	Arnold and Qiu, 1984	gas phase; Entropy change calculated or estimated; M

(  2) +  = (  3)

By formula: (NO₃^-  2HNO₃) + HNO₃ = (NO₃^-  3HNO₃)

Quantity	Value	Units	Method	Reference	Comment
rH°	16.1 ± 1.0	kcal/mol	TDAs	Davidson, Fehsenfeld, et al., 1977	gas phase; B,M
rH°	13.9 ± 1.4	kcal/mol	TDAs	Wlodek, Luczynski, et al., 1980	gas phase; B,M
rH°	16.0	kcal/mol	ATM	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M
rH°	16.0	kcal/mol	HPMS	Lee, Keesee, et al., 1980	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
rS°	25.	cal/mol*K	N/A	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M
rS°	28.9	cal/mol*K	FA	Davidson, Fehsenfeld, et al., 1977	gas phase; M
rS°	26.7	cal/mol*K	HPMS	Wlodek, Luczynski, et al., 1980	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
rG°	7.4 ± 2.2	kcal/mol	TDAs	Davidson, Fehsenfeld, et al., 1977	gas phase; B
rG°	5.90 ± 0.40	kcal/mol	TDAs	Wlodek, Luczynski, et al., 1980	gas phase; B
rG°	6.9	kcal/mol	FA	Fehsenfeld, Howard, et al., 1975	gas phase; M

Free energy of reaction

rG° (kcal/mol)	T (K)	Method	Reference	Comment
10.2	233.	ATM	Arnold, Viggiano, et al., 1982	gas phase; Entropy change calculated or estimated; M

(  3) +  = (  4)

By formula: (NO₃^-  3HNO₃) + HNO₃ = (NO₃^-  4HNO₃)

Quantity	Value	Units	Method	Reference	Comment
rH°	9.3 ± 1.3	kcal/mol	TDAs	Wlodek, Luczynski, et al., 1980	gas phase; B,M
Quantity	Value	Units	Method	Reference	Comment
rS°	19.9	cal/mol*K	HPMS	Wlodek, Luczynski, et al., 1980	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
rG°	3.20 ± 0.40	kcal/mol	TDAs	Wlodek, Luczynski, et al., 1980	gas phase; B
rG°	6.9 ± 1.0	kcal/mol	IMRE	Fehsenfeld, Howard, et al., 1975	gas phase; B

(  4) +  = (  5)

By formula: (NO₃^-  4HNO₃) + HNO₃ = (NO₃^-  5HNO₃)

Quantity	Value	Units	Method	Reference	Comment
rH°	7.4 ± 1.2	kcal/mol	TDAs	Wlodek, Luczynski, et al., 1980	gas phase; B,M
Quantity	Value	Units	Method	Reference	Comment
rS°	18.6	cal/mol*K	HPMS	Wlodek, Luczynski, et al., 1980	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
rG°	1.9 ± 1.0	kcal/mol	TDAs	Wlodek, Luczynski, et al., 1980	gas phase; B

(  5) +  = (  6)

By formula: (NO₃^-  5HNO₃) + HNO₃ = (NO₃^-  6HNO₃)

Quantity	Value	Units	Method	Reference	Comment
rH°	4.60 ± 0.90	kcal/mol	TDAs	Wlodek, Luczynski, et al., 1980	gas phase; B,M
Quantity	Value	Units	Method	Reference	Comment
rS°	7.3	cal/mol*K	HPMS	Wlodek, Luczynski, et al., 1980	gas phase; Entropy change is questionable; M
Quantity	Value	Units	Method	Reference	Comment
rG°	2.40 ± 0.70	kcal/mol	TDAs	Wlodek, Luczynski, et al., 1980	gas phase; B

 +  = (  )

By formula: Na⁺ + HNO₃ = (Na⁺  HNO₃)

Quantity	Value	Units	Method	Reference	Comment
rH°	20.6	kcal/mol	FA	Perry, Rowe, et al., 1980	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
rS°	20.3	cal/mol*K	FA	Perry, Rowe, et al., 1980	gas phase; M

References

Go To: Top, Ion clustering data, Notes

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

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]

Arnold, Viggiano, et al., 1982
Arnold, F.; Viggiano, A.A.; Schlager, H., Implications for Trace Gases and Aerosols of Large Negative Ions Clusters in the Stratosphere, Nature, 1982, 297, 5865, 371, https://doi.org/10.1038/297371a0 . [all data]

Wlodek, Luczynski, et al., 1980
Wlodek, S.; Luczynski, Z.; Wincel, H., Stabilities of gas-phase NO₃-.(HNO₃)n,n <= 6, clusters, Int. J. Mass Spectrom. Ion Phys., 1980, 35, 39. [all data]

Lee, Keesee, et al., 1980
Lee, N.; Keesee, R.G.; Castleman, A.W., Jr., The properties of clusters in the gas phase. IV. Complexes of H₂O and HNO_x clustering on NO_x-, J. Chem. Phys., 1980, 72, 1089. [all data]

Arnold and Qiu, 1984
Arnold, F.; Qiu, S., Upper Stratosphere Negative Ion Composition Measurements and Infrared Trace Gas Abundances, Planet. Space Sci., 1984, 32, 2, 169, https://doi.org/10.1016/0032-0633(84)90151-X . [all data]

Fehsenfeld, Howard, et al., 1975
Fehsenfeld, F.C.; Howard, C.J.; Schmeltkopf, A.L., Gas Phase Ion Chemistry of HNO3, J. Chem. Phys., 1975, 63, 7, 2835, https://doi.org/10.1063/1.431722 . [all data]

Perry, Rowe, et al., 1980
Perry, R.A.; Rowe, B.R.; Viggiano, A.A.; Albritton, D.L.; Ferguson, E.E.; Fehsenfeld, F.C., Laboratory Measurements of Stratospheric Sodium Ion Measurements, Geophys. Res. Lett., 1980, 7, 9, 693, https://doi.org/10.1029/GL007i009p00693 . [all data]

Notes

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• Symbols used in this document:
  

  T	Temperature
  rG°	Free energy of reaction at standard conditions
  rH°	Enthalpy of reaction at standard conditions
  rS°	Entropy of reaction at standard conditions

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