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
  • Phase change data
  • Gas phase ion energetics data
  • Ion clustering data
  • IR Spectrum
  • References
  • Notes
• Other data available:
  • Reaction thermochemistry data: reactions 1 to 50, reactions 51 to 100, reactions 101 to 150, reactions 151 to 158
  • Henry's Law data
  • Mass spectrum (electron ionization)
  • Constants of diatomic molecules
• Data at other public NIST sites:
  • Microwave spectra (on physics lab web site)
  • Gas Phase Kinetics Database
• Options:
  • Switch to SI units

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• NIST / TRC Web Thermo Tables, professional edition (thermophysical and thermochemical data)

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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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View table.

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 as indicated in comments:
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
AC - William E. Acree, Jr., James S. Chickos

Enthalpy of vaporization

Antoine Equation Parameters

log₁₀(P) = A − (B / (T + C))
    P = vapor pressure (atm)
    T = temperature (K)

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Enthalpy of sublimation

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)

IR Spectrum

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Data compiled by: Coblentz Society, Inc.

• GAS (200 mmHg DILUTED TO A TOTAL PRESSURE OF 600 mmHg WITH N2); DOW KBr FOREPRISM; DIGITIZED BY NIST FROM HARD COPY (FROM TWO SEGMENTS); 4 cm^-1 resolution
• GAS (200 mmHg, N2 ADDED, TOTAL PRESSURE 600 mmHg); DOW KBr FOREPRISM-GRATING; DIGITIZED BY NIST FROM HARD COPY (FROM TWO SEGMENTS); 2 cm^-1 resolution

References

Go To: Top, Gas phase thermochemistry data, Phase change data, Gas phase ion energetics data, Ion clustering data, IR Spectrum, 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]

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Beckmann, E.; Waentig, P., Cryoscopic Measurements at Low Temperatures, Z. Anorg. Chem., 1910, 67, 17. [all data]

Henderson, Lewis, et al., 1986
Henderson, C.; Lewis, D.G.; Prichard, P.C.; Staveley, L.A.K.; Fonseca, I.M.A.; Lobo, L.Q., Some thermodynamic properties of hydrogen chloride and deuterium chloride, J. Chem. Thermodyn., 1986, 18, 1077. [all data]

Giauque and Wiebe, 1928
Giauque, W.F.; Wiebe, R., THE ENTROPY OF HYDROGEN CHLORIDE. HEAT CAPACITY FROM 16°K. TO BOILING POINT. HEAT OF VAPORIZATION. VAPOR PRESSURES OF SOLID AND LIQUID, J. Am. Chem. Soc., 1928, 50, 1, 101-122, https://doi.org/10.1021/ja01388a013 . [all data]

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Stull, Daniel R., Vapor Pressure of Pure Substances. Organic and Inorganic Compounds, Ind. Eng. Chem., 1947, 39, 4, 517-540, https://doi.org/10.1021/ie50448a022 . [all data]

Ser and Larher, 1990
Ser, Frederic; Larher, Yves, Sublimation pressures of hydrogen chloride, The Journal of Chemical Thermodynamics, 1990, 22, 4, 407-412, https://doi.org/10.1016/0021-9614(90)90129-E . [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]

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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]

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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]

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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]

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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]

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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]

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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]

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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]

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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]

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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]

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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]

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Notes

Go To: Top, Gas phase thermochemistry data, Phase change data, Gas phase ion energetics data, Ion clustering data, IR Spectrum, References

• Symbols used in this document:
  

  AE	Appearance energy
  IE (evaluated)	Recommended ionization energy
  Pc	Critical pressure
  Ptriple	Triple point pressure
  S°gas,1 bar	Entropy of gas at standard conditions (1 bar)
  Tc	Critical temperature
  Tfus	Fusion (melting) point
  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
  ΔsubH	Enthalpy of sublimation
  ΔvapH	Enthalpy of vaporization

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