Hydrogen chloride
- Formula: ClH
- Molecular weight: 36.461
- IUPAC Standard InChIKey: VEXZGXHMUGYJMC-UHFFFAOYSA-N
- 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:
- 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
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Gas phase ion energetics data
Go To: Top, References, Notes
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)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
IE (evaluated) | 12.744 ± 0.009 | eV | N/A | N/A | L |
Quantity | Value | Units | Method | Reference | Comment |
Proton affinity (review) | 556.9 | kJ/mol | N/A | Hunter and Lias, 1998 | HL |
Quantity | Value | Units | Method | Reference | Comment |
Gas basicity | 530.1 | kJ/mol | N/A | Hunter and Lias, 1998 | HL |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
12.790 | PE | Wang, Dillon, et al., 1984 | LBLHLM |
12.752 ± 0.006 | PE | Pennetreau, Natalis, et al., 1983 | LBLHLM |
12.748 | PE | Von Niessen, Asbrink, et al., 1982 | LBLHLM |
12.747 ± 0.002 | PE | Natalis, Pennetreau, et al., 1982 | LBLHLM |
12.75 | PE | Kimura, Katsumata, et al., 1981 | LLK |
12.72 ± 0.03 | PI | Tiedemann, Anderson, et al., 1979 | LLK |
12.748 | EVAL | Huber and Herzberg, 1979 | LLK |
12.748 ± 0.005 | PE | Weiss, Lawrence, et al., 1970 | RDSH |
12.74 ± 0.01 | PE | Lempka, Passmore, et al., 1968 | RDSH |
12.742 ± 0.010 | PI | Nicholson, 1965 | RDSH |
12.74 ± 0.01 | PI | Watanabe, 1957 | RDSH |
Appearance energy determinations
Ion | AE (eV) | Other Products | Method | Reference | Comment |
---|---|---|---|---|---|
Cl+ | 17.34 ± 0.01 | H | PI | Krauss, Walker, et al., 1968 | RDSH |
H+ | 14.5 | Cl- | EI | Fox, 1957 | RDSH |
De-protonation reactions
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 1394.9 | kJ/mol | N/A | Martin and Hepburn, 1998 | gas phase; Given: ΔHacid(0K)=116288.7±0.6 cm-1, or 332.486±0.002 kcal/mol; B |
ΔrH° | 1396. ± 8.8 | kJ/mol | G+TS | Fujio, McIver, et al., 1981 | gas phase; value altered from reference due to change in acidity scale; B |
ΔrH° | 1377.0 | kJ/mol | N/A | Check, Faust, et al., 2001 | gas phase; FeCC-(q); ; ΔS(EA)=5.0; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 1372.8 ± 0.42 | kJ/mol | H-TS | Martin and Hepburn, 1998 | gas phase; Given: ΔHacid(0K)=116288.7±0.6 cm-1, or 332.486±0.002 kcal/mol; B |
ΔrG° | 1374. ± 8.4 | kJ/mol | IMRE | Fujio, McIver, et al., 1981 | gas phase; value altered from reference due to change in acidity scale; B |
ΔrG° | 1354.4 | kJ/mol | N/A | Check, Faust, et al., 2001 | gas phase; FeCC-(q); ; ΔS(EA)=5.0; B |
References
Go To: Top, 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.
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]
Notes
Go To: Top, Gas phase ion energetics data, References
- Symbols used in this document:
AE Appearance energy IE (evaluated) Recommended ionization energy 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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