Hydrogen bromide
- Formula: BrH
- Molecular weight: 80.912
- IUPAC Standard InChIKey: CPELXLSAUQHCOX-UHFFFAOYSA-N
- CAS Registry Number: 10035-10-6
- 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. - Other names: Hydrobromic acid; Anhydrous hydrobromic acid; HBr; Hydrogen bromide, anhydrous-; Acide bromhydrique; Acido bromidrico; Bromowodor; Bromwasserstoff; Broomwaterstof; UN 1048; UN 1788; Hydrogen monobromide
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- Information on this page:
- Other data available:
- Gas phase thermochemistry data
- Phase change data
- Reaction thermochemistry data: reactions 1 to 50, reactions 51 to 76
- Henry's Law data
- Constants of diatomic molecules
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Gas phase ion energetics data
Go To: Top, Ion clustering data, IR Spectrum, Mass spectrum (electron ionization), 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
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 HBr+ (ion structure unspecified)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
IE (evaluated) | 11.68 ± 0.03 | eV | N/A | N/A | L |
Quantity | Value | Units | Method | Reference | Comment |
Proton affinity (review) | 139.6 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
Quantity | Value | Units | Method | Reference | Comment |
Gas basicity | 133.3 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
11.71 | PE | Kimura, Katsumata, et al., 1981 | LLK |
11.66 ± 0.02 | PI | Tiedemann, Anderson, et al., 1979 | LLK |
11.67 | EVAL | Huber and Herzberg, 1979 | LLK |
11.645 ± 0.005 | PE | Delwiche, Natalis, et al., 1973 | LLK |
11.677 ± 0.004 | DER | Haugh and Bayes, 1971 | LLK |
11.67 ± 0.01 | PE | Lempka, Passmore, et al., 1968 | RDSH |
11.71 ± 0.01 | PE | Frost, McDowell, et al., 1967 | RDSH |
11.68 ± 0.03 | PI | Watanabe, 1957 | RDSH |
De-protonation reactions
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 323.540 ± 0.050 | kcal/mol | D-EA | Blondel, Cacciani, et al., 1989 | gas phase; reported: 27129.170±0.015 cm-1; B |
ΔrH° | 323.4 ± 2.1 | kcal/mol | G+TS | Taft and Bordwell, 1988 | gas phase; B |
ΔrH° | 320.60 | kcal/mol | N/A | Check, Faust, et al., 2001 | gas phase; F-; ; ΔS(acid)=19.2; ΔS(EA)=6.4; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 318.30 ± 0.15 | kcal/mol | H-TS | Blondel, Cacciani, et al., 1989 | gas phase; reported: 27129.170±0.015 cm-1; B |
ΔrG° | 318.2 ± 2.0 | kcal/mol | IMRE | Taft and Bordwell, 1988 | gas phase; B |
ΔrG° | 315.40 | kcal/mol | N/A | Check, Faust, et al., 2001 | gas phase; F-; ; ΔS(acid)=19.2; ΔS(EA)=6.4; B |
Ion clustering data
Go To: Top, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), 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:
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- + HBr = (Br- • HBr)
Bond type: Hydrogen bond (negative ion to hydride)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 20.6 ± 2.0 | kcal/mol | TDAs | Caldwell and Kebarle, 1985 | gas phase; B,M |
ΔrH° | 17.5 | kcal/mol | FA | Davidson, Fehsenfeld, et al., 1977 | gas phase; From thermochemical cycle,switching reaction(Br-/NO3-HNO3/HBr); DG>, ΔrH>; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 22.3 | cal/mol*K | PHPMS | Caldwell and Kebarle, 1985 | gas phase; M |
ΔrS° | 22. | cal/mol*K | FA | Davidson, Fehsenfeld, et al., 1977 | gas phase; From thermochemical cycle,switching reaction(Br-/NO3-HNO3/HBr); DG>, ΔrH>; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 13.9 ± 2.6 | kcal/mol | TDAs | Caldwell and Kebarle, 1985 | gas phase; B |
Free energy of reaction
ΔrG° (kcal/mol) | T (K) | Method | Reference | Comment |
---|---|---|---|---|
9.4 | 367. | FA | Davidson, Fehsenfeld, et al., 1977 | gas phase; From thermochemical cycle,switching reaction(Br-/NO3-HNO3/HBr); DG>, ΔrH>; M |
By formula: (Br- • HBr) + HBr = (Br- • 2HBr)
Bond type: Hydrogen bond (negative ion to hydride)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 11.0 | kcal/mol | PHPMS | Caldwell and Kebarle, 1985 | gas phase; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 17.0 | cal/mol*K | PHPMS | Caldwell and Kebarle, 1985 | gas phase; M |
By formula: (Br- • O2S) + HBr = (Br- • HBr • O2S)
Bond type: Hydrogen bond (negative ion to hydride)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 12.2 | kcal/mol | PHPMS | Caldwell and Kebarle, 1985 | gas phase; From thermochemical cycle,switching reaction(Br- HBr)SO2; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 19.2 | cal/mol*K | PHPMS | Caldwell and Kebarle, 1985 | gas phase; From thermochemical cycle,switching reaction(Br- HBr)SO2; M |
By formula: CH3+ + HBr = (CH3+ • HBr)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 55.4 | kcal/mol | PHPMS | McMahon, Heinis, et al., 1988 | gas phase; switching reaction(CH3+)N2, Entropy change calculated or estimated, uses MCA(N2) = 48.3 kcal/mol; Foster, Williamson, et al., 1974; M |
By formula: HBr+ + HBr = (HBr+ • HBr)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 23. | kcal/mol | PI | Tiedemann, Anderson, et al., 1979 | gas phase; M |
By formula: I- + HBr = (I- • HBr)
Bond type: Hydrogen bond (negative ion to hydride)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 16.1 ± 2.0 | kcal/mol | TDEq | Caldwell and Kebarle, 1985 | gas phase; B,M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 19.6 | cal/mol*K | PHPMS | Caldwell and Kebarle, 1985 | gas phase; switching reaction(I-)SO2; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 10.2 ± 2.6 | kcal/mol | TDEq | Caldwell and Kebarle, 1985 | gas phase; B |
Free energy of reaction
ΔrG° (kcal/mol) | T (K) | Method | Reference | Comment |
---|---|---|---|---|
10.2 | 300. | PHPMS | Caldwell and Kebarle, 1985 | gas phase; switching reaction(I-)SO2; M |
By formula: NO3- + HBr = (NO3- • HBr)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrS° | 23. | cal/mol*K | N/A | Davidson, Fehsenfeld, et al., 1977 | gas phase; switching reaction(NO3-)HNO3, Entropy change calculated or estimated, DG<, ΔrH<; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 17.4 ± 3.9 | kcal/mol | TDEq | Davidson, Fehsenfeld, et al., 1977 | gas phase; Anchored to HBr..Br- in Caldwell and Kebarle, 1985.; B |
Free energy of reaction
ΔrG° (kcal/mol) | T (K) | Method | Reference | Comment |
---|---|---|---|---|
12.7 | 367. | FA | Davidson, Fehsenfeld, et al., 1977 | gas phase; switching reaction(NO3-)HNO3, Entropy change calculated or estimated, DG<, ΔrH<; M |
By formula: (NO3- • HNO3) + HBr = (NO3- • HBr • HNO3)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 16.0 | kcal/mol | FA | Davidson, Fehsenfeld, et al., 1977 | gas phase; switching reaction(NO3-)2HNO3; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 22.9 | cal/mol*K | FA | Davidson, Fehsenfeld, et al., 1977 | gas phase; switching reaction(NO3-)2HNO3; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 9.2 | kcal/mol | FA | Davidson, Fehsenfeld, et al., 1977 | gas phase; switching reaction(NO3-)2HNO3; M |
IR Spectrum
Go To: Top, Gas phase ion energetics data, Ion clustering data, Mass spectrum (electron ionization), 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: Coblentz Society, Inc.
Gas Phase Spectrum
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Notice: Except where noted, spectra from this collection were measured on dispersive instruments, often in carefully selected solvents, and hence may differ in detail from measurements on FTIR instruments or in other chemical environments. More information on the manner in which spectra in this collection were collected can be found here.
Notice: Concentration information is not available for this spectrum and, therefore, molar absorptivity values cannot be derived.
Additional Data
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Download spectrum in JCAMP-DX format.
Owner | COBLENTZ SOCIETY Collection (C) 2018 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved. |
---|---|
Origin | DOW CHEMICAL COMPANY |
Source reference | COBLENTZ NO. 8757 |
Date | 1964 |
State | GAS (600 mmHg DILUTED TO A TOTAL PRESSURE OF 600 mmHg WITH N2) |
Instrument | DOW KBr FOREPRISM |
Instrument parameters | GRATING CHANGED AT 5.0, 7.5, 15.0 MICRON |
Path length | 5 CM |
Resolution | 4 |
Sampling procedure | TRANSMISSION |
Data processing | DIGITIZED BY NIST FROM HARD COPY (FROM TWO SEGMENTS) |
Mass spectrum (electron ionization)
Go To: Top, Gas phase ion energetics data, Ion clustering data, IR Spectrum, 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: NIST Mass Spectrometry Data Center, William E. Wallace, director
Spectrum
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Additional Data
View image of digitized spectrum (can be printed in landscape orientation).
Due to licensing restrictions, this spectrum cannot be downloaded.
Owner | NIST Mass Spectrometry Data Center Collection (C) 2014 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved. |
---|---|
Origin | Chemical Concepts |
NIST MS number | 157480 |
References
Go To: Top, Gas phase ion energetics data, Ion clustering data, IR Spectrum, 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.
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]
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]
Delwiche, Natalis, et al., 1973
Delwiche, J.; Natalis, P.; Momigny, J.; Collin, J.E.,
On the photoelectron spectra of HBr DBr,
J. Electron Spectrosc. Relat. Phenom., 1973, 1, 219. [all data]
Haugh and Bayes, 1971
Haugh, M.J.; Bayes, K.D.,
Predissociation and dissociation energy of HBr+,
J. Phys. Chem., 1971, 75, 1472. [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]
Frost, McDowell, et al., 1967
Frost, D.C.; McDowell, C.A.; Vroom, D.A.,
Photoelectron spectra of the halogens and the hydrogen halides,
J. Chem. Phys., 1967, 46, 4255. [all data]
Watanabe, 1957
Watanabe, K.,
Ionization potentials of some molecules,
J. Chem. Phys., 1957, 26, 542. [all data]
Blondel, Cacciani, et al., 1989
Blondel, C.; Cacciani, P.; Delsart, C.; Trainham, R.,
High Resolution Determination of the Electron Affinity of Fluorine and Bromine using Crossed Ion and Laser Beams,
Phys. Rev. A, 1989, 40, 7, 3698, https://doi.org/10.1103/PhysRevA.40.3698
. [all data]
Taft and Bordwell, 1988
Taft, R.W.; Bordwell, F.G.,
Structural and Solvent Effects Evaluated from Acidities Measured in Dimethyl Sulfoxide and in the Gas Phase,
Acc. Chem. Res., 1988, 21, 12, 463, https://doi.org/10.1021/ar00156a005
. [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]
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]
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]
Notes
Go To: Top, Gas phase ion energetics data, Ion clustering data, IR Spectrum, Mass spectrum (electron ionization), References
- Symbols used in this document:
IE (evaluated) Recommended ionization energy T Temperature 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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