Hydrogen chloride

• Formula: ClH
• Molecular weight: 36.461
• IUPAC Standard InChI: InChI=1S/ClH/h1H Copy

  
• IUPAC Standard InChIKey: VEXZGXHMUGYJMC-UHFFFAOYSA-N Copy
• CAS Registry Number: 7647-01-0
• Chemical structure:
  This structure is also available as a 2d Mol file or as a computed 3d SD file
  The 3d structure may be viewed using Java or Javascript.
• Isotopologues:
  • Hydrochloric acid-d
• Other names: Hydrochloric ccid; Anhydrous hydrochloric acid; Chlorohydric acid; Hydrochloric acid gas; Hydrochloride; Muriatic acid; Salzsaeure; HCl; Hydrochloric acid, anhydrous; Hydrogen-chloride-anhydrous-; Acide chlorhydrique; Acido cloridrico; Chloorwaterstof; Chlorowodor; Chlorwasserstoff; NA 1789; Spirits of salt; UN 1050; UN 1789; UN 2186; Anhydrous hydrogen chloride; Hydrogen chloride (acid); Marine acid; Soldering acid; Spirit of salt; Spirits of salts; Hydrogen chloride (HCl); NSC 77365; Hydrochloric acid
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Gas phase thermochemistry data
  • Gas phase ion energetics data
  • Ion clustering data
  • Mass spectrum (electron ionization)
  • References
  • Notes
• Other data available:
  • Phase change data
  • Reaction thermochemistry data: reactions 1 to 50, reactions 51 to 100, reactions 101 to 150, reactions 151 to 158
  • Henry's Law data
  • IR Spectrum
  • Constants of diatomic molecules
• Data at other public NIST sites:
  • Microwave spectra (on physics lab web site)
  • 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 (J/mol*K)
    H° = standard enthalpy (kJ/mol)
    S° = standard entropy (J/mol*K)
    t = temperature (K) / 1000.

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

Data compiled as indicated in comments:
B - John E. Bartmess
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron

View reactions leading to HCl⁺ (ion structure unspecified)

Ionization energy determinations

Appearance energy determinations

De-protonation reactions

 +  =

By formula: Cl^- + H⁺ = HCl

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:
B - John E. Bartmess
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias

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^- + HCl = (Br^- • HCl)

Bond type: Hydrogen bond (negative ion to hydride)

( • ) +  = ( • 2)

By formula: (Br^- • HCl) + HCl = (Br^- • 2HCl)

Bond type: Hydrogen bond (negative ion to hydride)

( • ) +  = ( •  • )

By formula: (Br^- • O₂S) + HCl = (Br^- • HCl • O₂S)

Bond type: Hydrogen bond (negative ion to hydride)

 +  = ( • )

By formula: CH₃⁺ + HCl = (CH₃⁺ • HCl)

C₆H₆⁺ +  = (C₆H₆⁺ • )

By formula: C₆H₆⁺ + HCl = (C₆H₆⁺ • HCl)

 +  = ( • )

By formula: Cl^- + HCl = (Cl^- • HCl)

Bond type: Hydrogen bond (negative ion to hydride)

( • ) +  = ( • 2)

By formula: (Cl^- • HCl) + HCl = (Cl^- • 2HCl)

Bond type: Hydrogen bond (negative ion to hydride)

( • 2) +  = ( • 3)

By formula: (Cl^- • 2HCl) + HCl = (Cl^- • 3HCl)

Bond type: Hydrogen bond (negative ion to hydride)

( • 3) +  = ( • 4)

By formula: (Cl^- • 3HCl) + HCl = (Cl^- • 4HCl)

Bond type: Hydrogen bond (negative ion to hydride)

( •  • ) +  = ( • 2 • )

By formula: (Cl^- • HCl • H₂O) + HCl = (Cl^- • 2HCl • H₂O)

Bond type: Hydrogen bond (negative ion to hydride)

( • ) +  = ( •  • )

By formula: (Cl^- • H₂O) + HCl = (Cl^- • HCl • H₂O)

Bond type: Hydrogen bond (negative ion to hydride)

( • 2) +  = ( •  • 2)

By formula: (Cl^- • 2H₂O) + HCl = (Cl^- • HCl • 2H₂O)

Bond type: Hydrogen bond (negative ion to hydride)

( • ) +  = ( •  • )

By formula: (Cl^- • O₂S) + HCl = (Cl^- • HCl • O₂S)

Bond type: Hydrogen bond (negative ion to hydride)

 +  = ( • )

By formula: F^- + HCl = (F^- • HCl)

Bond type: Hydrogen bond (negative ion to hydride)

HCl⁺ +  = (HCl⁺ • )

By formula: HCl⁺ + HCl = (HCl⁺ • HCl)

HO₄S^- +  = (HO₄S^- • )

By formula: HO₄S^- + HCl = (HO₄S^- • HCl)

 +  = ( • )

By formula: I^- + HCl = (I^- • HCl)

Bond type: Hydrogen bond (negative ion to hydride)

 +  = ( • )

By formula: Na⁺ + HCl = (Na⁺ • HCl)

Mass spectrum (electron ionization)

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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: NIST Mass Spectrometry Data Center, William E. Wallace, director

Spectrum

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Additional Data

References

Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, Ion clustering data, Mass spectrum (electron ionization), Notes

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

Cox, Wagman, et al., 1984
Cox, J.D.; Wagman, D.D.; Medvedev, V.A., CODATA Key Values for Thermodynamics, Hemisphere Publishing Corp., New York, 1984, 1. [all data]

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

Wang, Dillon, et al., 1984
Wang, R.-G.; Dillon, M.A.; Spence, D., Electron spectroscopy of hydrogen chloride from 5 to 19 eV, J. Chem. Phys., 1984, 80, 63. [all data]

Pennetreau, Natalis, et al., 1983
Pennetreau, P.; Natalis, P.; Longton, L.; Collin, J.E., Ionization energies for the vibronic transitions from DCl X¹Σ⁺(v" = 0) to DCl⁺ X²Π(v' = 0-18) and A²Σ⁺ (v' = 0-17) determined by photoelectron spectroscopy, J. Electron Spectrosc. Relat. Phenom., 1983, 28, 295. [all data]

Von Niessen, Asbrink, et al., 1982
Von Niessen, W.; Asbrink, L.; Bieri, G., 30.4 nm He(II) Photoelectron spectra of organic molecules. Part VI. Halogeno-compounds (C,H,X: X = Cl, Br, I), J. Electron Spectrosc. Relat. Phenom., 1982, 26, 173. [all data]

Natalis, Pennetreau, et al., 1982
Natalis, P.; Pennetreau, P.; Longton, L.; Collin, J.E., Ionisation energy values for the vibronic transitions from HCl X¹Σ⁺ (v" = 0) to HCl⁺ ionic states X²Π (v' = 0-13) and A²Σ⁺ (v' = 0-12), determined by photoelectron spectroscopy, J. Electron Spectrosc. Relat. Phenom., 1982, 27, 267. [all data]

Kimura, Katsumata, et al., 1981
Kimura, K.; Katsumata, S.; Achiba, Y.; Yamazaki, T.; Iwata, S., Ionization energies, Ab initio assignments, and valence electronic structure for 200 molecules in Handbook of HeI Photoelectron Spectra of Fundamental Organic Compounds, Japan Scientific Soc. Press, Tokyo, 1981. [all data]

Tiedemann, Anderson, et al., 1979
Tiedemann, P.W.; Anderson, S.L.; Ceyer, S.T.; Hirooka, T.; Ng, C.Y.; Mahan, B.H.; Lee, Y.T., Proton affinities of hydrogen halides determined by the molecular beam photoionization method, J. Chem. Phys., 1979, 71, 605. [all data]

Huber and Herzberg, 1979
Huber, K.P.; Herzberg, G., Molecular Spectra and Molecular Structure. IV. Constants of Diatomic Molecules,, Van Nostrand Reinhold Co., 1979, ,1. [all data]

Weiss, Lawrence, et al., 1970
Weiss, M.J.; Lawrence, G.M.; Young, R.A., Photoelectron spectroscopy of HCI and DCI using molecular beams, J. Chem. Phys., 1970, 52, 2867. [all data]

Lempka, Passmore, et al., 1968
Lempka, H.J.; Passmore, T.R.; Price, W.C., The photoelectron spectra and ionized states of the halogen acids, Proc. Roy. Soc. (London), 1968, A304, 53. [all data]

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

Watanabe, 1957
Watanabe, K., Ionization potentials of some molecules, J. Chem. Phys., 1957, 26, 542. [all data]

Krauss, Walker, et al., 1968
Krauss, M.; Walker, J.A.; Dibeler, V.H., Mass spectrometric study of photoionization. X. Hydrogen chloride and methyl halides, J. Res. NBS, 1968, 72A, 281. [all data]

Fox, 1957
Fox, R.E., Negative ion formation in hydrogen chloride by electron impact, J. Chem. Phys., 1957, 26, 1281. [all data]

Martin and Hepburn, 1998
Martin, J.D.D.; Hepburn, J.W., Determination of bond dissociation energies by threshold ion-pair production spectroscopy: An improved D-0(HCl), J. Chem. Phys., 1998, 109, 19, 8139-8142, https://doi.org/10.1063/1.477476 . [all data]

Fujio, McIver, et al., 1981
Fujio, M.; McIver, R.T., Jr.; Taft, R.W., Effects on the acidities of phenols from specific substituent-solvent interactions. Inherent substituent parameters from gas phase acidities, J. Am. Chem. Soc., 1981, 103, 4017. [all data]

Check, Faust, et al., 2001
Check, C.E.; Faust, T.O.; Bailey, J.M.; Wright, B.J.; Gilbert, T.M.; Sunderlin, L.S., Addition of Polarization and Diffuse Functions to the LANL2DZ Basis Set for P-Block Elements, J. Phys. Chem. A,, 2001, 105, 34, 8111, https://doi.org/10.1021/jp011945l . [all data]

Caldwell and Kebarle, 1985
Caldwell, G.; Kebarle, P., The hydrogen bond energies of the bihalide ions XHX- and YHX-, Can. J. Chem., 1985, 63, 1399. [all data]

McMahon, Heinis, et al., 1988
McMahon, T.; Heinis, T.; Nicol, G.; Hovey, J.K.; Kebarle, P., Methyl Cation Affinities, J. Am. Chem. Soc., 1988, 110, 23, 7591, https://doi.org/10.1021/ja00231a002 . [all data]

Foster, Williamson, et al., 1974
Foster, M.S.; Williamson, A.D.; Beauchamp, J.L., Photoionization mass spectrometry of trans-azomethane, Int. J. Mass Spectrom. Ion Phys., 1974, 15, 429. [all data]

Walters, Grover, et al., 1985
Walters, E.A.; Grover, J.R.; White, M.G.; Hui, E.T., On the Structure and Thermochemistry of the van der Waals Molecule C6H6.HCl and its Photoion (C6H6.HCl)+, J. Phys. Chem., 1985, 89, 18, 3814, https://doi.org/10.1021/j100264a009 . [all data]

Metz, Kitsopoulos, et al., 1988
Metz, R.B.; Kitsopoulos, T.; Weaver, A.; Neumark, D.M., Study of the Transition State Region in the Cl+HCl Reaction by Photoelectron Spectroscopy of ClHCl-, J. Chem. Phys., 1988, 88, 2, 1463, https://doi.org/10.1063/1.454218 . [all data]

Larson and McMahon, 1984
Larson, J.W.; McMahon, T.B., Hydrogen bonding in gas phase anions. An experimental investigation of the interaction between chloride ion and bronsted acids from ICR chloride exchange equilibria, J. Am. Chem. Soc., 1984, 106, 517. [all data]

Yamdagni and Kebarle, 1974
Yamdagni, R.; Kebarle, P., The hydrogen bond energies in ClHCl- and Cl-(HCl)n, Can. J. Chem., 1974, 52, 2449. [all data]

Upschulte, Evans, et al., 1986
Upschulte, B.L.; Evans, D.H.; Keesee, R.G.; Castleman, A.W., Unpublished results, referred to in Keesee and Castleman, 1986, 1986. [all data]

Keesee and Castleman, 1980
Keesee, R.G.; Castleman, A.W., Jr., Gas phase studies of hydration complexes of Cl- and I- and comparison to electrostatic calculations in the gas phase, Chem. Phys. Lett., 1980, 74, 139. [all data]

Larson and McMahon, 1984, 2
Larson, J.W.; McMahon, T.B., Gas phase negative ion chemistry of alkylchloroformates, Can. J. Chem., 1984, 62, 675. [all data]

French, Ikuta, et al., 1982
French, M.A.; Ikuta, S.; Kebarle, P., Hydrogen bonding of O-H and C-H hydrogen donors to Cl^-. Results from mass spectrometric measurement of the ion-molecule equilibria RH + Cl^- = RHCl^-, Can. J. Chem., 1982, 60, 1907. [all data]

Larson and McMahon, 1987
Larson, J.W.; McMahon, T.B., Isotope Effects in Proton Transfer Reactions. An Ion Cyclotron Resonance Determination of the Equilibrium Deuterium Isotope Effect in the Bichloride Ion, J. Phys. Chem., 1987, 91, 3, 554, https://doi.org/10.1021/j100287a013 . [all data]

Larson and McMahon, 1984, 3
Larson, J.W.; McMahon, T.B., Fluoride and chloride affinities of main group oxides, fluorides, oxofluorides, and alkyls. Quantitative scales of lewis acidities from ion cyclotron resonance halide-exchange equilibria, J. Phys. Chem., 1984, 88, 1083. [all data]

Larson and McMahon, 1985
Larson, J.W.; McMahon, T.B., Fluoride and chloride affinities of the main group oxides, fluorides, oxofluorides, and alkyls. Quantitative scales of lewis acidities from ICR halide exchange equilibria, J. Am. Chem. Soc., 1985, 107, 766. [all data]

Bohringer, Fahey, et al., 1984
Bohringer, H.; Fahey, D.W.; Fehsenfeld, F.C.; Ferguson, E.E., Bond energies of the molecules H₂O, SO₂, H₂O₂, and HCl to various atmospheric negative ions, J. Chem. Phys., 1984, 81, 2805. [all data]

Keesee, Lee, et al., 1980
Keesee, R.G.; Lee, N.; Castleman, A.W., Jr., Properties of clusters in the gas phase: V. Complexes of neutral molecules onto negative ions, J. Chem. Phys., 1980, 73, 2195. [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]

Keesee and Castleman, 1986
Keesee, R.G.; Castleman, A.W., Jr., Thermochemical data on Ggs-phase ion-molecule association and clustering reactions, J. Phys. Chem. Ref. Data, 1986, 15, 1011. [all data]

Notes

Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, Ion clustering data, Mass spectrum (electron ionization), References

• Symbols used in this document:
  

  AE	Appearance energy
  IE (evaluated)	Recommended ionization energy
  S°gas,1 bar	Entropy of gas at standard conditions (1 bar)
  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
  ΔrS°	Entropy of reaction at standard conditions

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