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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Phase change data
Go To: Top, Henry's Law data, Gas phase ion energetics data, References, Notes
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
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Tfus | 161.15 | K | N/A | Beckmann and Waentig, 1910 | Uncertainty assigned by TRC = 2. K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Ptriple | 0.13800 | bar | N/A | Henderson, Lewis, et al., 1986 | Uncertainty assigned by TRC = 0.00006 bar; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Tc | 324.68 | K | N/A | Henderson, Lewis, et al., 1986 | Uncertainty assigned by TRC = 0.03 K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Pc | 82.56 | bar | N/A | Henderson, Lewis, et al., 1986 | Uncertainty assigned by TRC = 0.0824 bar; VP measured up to 219 K and Pc determined from fitted Wagner equation; TRC |
Enthalpy of vaporization
ΔvapH (kJ/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
16.2 | 188. | C | Giauque and Wiebe, 1928 | AC |
Antoine Equation Parameters
log10(P) = A − (B / (T + C))
P = vapor pressure (bar)
T = temperature (K)
View plot Requires a JavaScript / HTML 5 canvas capable browser.
Temperature (K) | A | B | C | Reference | Comment |
---|---|---|---|---|---|
122.3 to 188.3 | 3.60765 | 535.172 | -39.847 | Stull, 1947 | Coefficents calculated by NIST from author's data. |
188.3 to 309.4 | 4.57389 | 868.358 | 1.754 | Stull, 1947 | Coefficents calculated by NIST from author's data. |
Enthalpy of sublimation
ΔsubH (kJ/mol) | Temperature (K) | Reference | Comment |
---|---|---|---|
19.7 | 127. | Ser and Larher, 1990 | Based on data from 121. to 133. K.; AC |
19.6 | 142. | Ser and Larher, 1990 | Based on data from 134. to 150. K.; AC |
Henry's Law data
Go To: Top, Phase change data, Gas phase ion energetics data, References, Notes
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)
kH(T) = k°H exp(d(ln(kH))/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(kH))/d(1/T) = Temperature dependence constant (K)
k°H (mol/(kg*bar)) | d(ln(kH))/d(1/T) (K) | Method | Reference | Comment |
---|---|---|---|---|
19. | 600. | Q | N/A | Only the tabulated data between T = 273. K and T = 303. K from missing citation was used to derive kH and -Δ kH/R. Above T = 303. K the tabulated data could not be parameterized by equation (reference missing) very well. The partial pressure of water vapor (needed to convert some Henry's law constants) was calculated using the formula given by missing citation. The quantities A and α from missing citation were assumed to be identical. |
2.0×10+6/KA | 9000. | T | N/A | For strong acids, the solubility is often expressed as kH = ([H+] * [A-]) / p(HA). To obtain the physical solubility of HA, the value has to be divided by the acidity constant KA. missing citation corrects erroneous data from missing citation. |
2500. | Q | N/A | Several references are given in the list of Henry's law constants but not assigned to specific species. | |
1.1 | 2000. | T | N/A | |
20. | C | N/A | ||
2.0×10+6/KA | 9000. | T | N/A | |
1500. | X | N/A | The value is taken from the compilation of solubilities by W. Asman (unpublished). | |
19. | 9000. | X | N/A | The value is taken from the compilation of solubilities by W. Asman (unpublished). |
170000./KA | X | N/A | The value is taken from the compilation of solubilities by W. Asman (unpublished). For strong acids, the solubility is often expressed as kH = ([H+] * [A-]) / p(HA). To obtain the physical solubility of HA, the value has to be divided by the acidity constant KA. |
Gas phase ion energetics data
Go To: Top, Phase change data, Henry's Law data, 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, 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.
Beckmann and Waentig, 1910
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]
Stull, 1947
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]
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, Phase change data, Henry's Law data, Gas phase ion energetics data, References
- Symbols used in this document:
AE Appearance energy IE (evaluated) Recommended ionization energy Pc Critical pressure Ptriple Triple point pressure Tc Critical temperature Tfus Fusion (melting) point d(ln(kH))/d(1/T) Temperature dependence parameter for Henry's Law constant k°H Henry's Law constant at 298.15K ΔrG° Free energy of reaction at standard conditions ΔrH° Enthalpy 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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