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:
- Reaction thermochemistry data: reactions 1 to 50, reactions 51 to 76
- Gas phase ion energetics data
- IR Spectrum
- Mass spectrum (electron ionization)
- Constants of diatomic molecules
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Gas phase thermochemistry data
Go To: Top, Phase change data, Henry's Law data, Ion clustering data, References, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔfH°gas | -36.29 ± 0.16 | kJ/mol | Review | Cox, Wagman, et al., 1984 | CODATA Review value |
ΔfH°gas | -36.44 | kJ/mol | Review | Chase, 1998 | Data last reviewed in September, 1965 |
Quantity | Value | Units | Method | Reference | Comment |
S°gas,1 bar | 198.700 ± 0.004 | J/mol*K | Review | Cox, Wagman, et al., 1984 | CODATA Review value |
S°gas,1 bar | 198.70 | J/mol*K | Review | Chase, 1998 | Data last reviewed in September, 1965 |
Gas Phase Heat Capacity (Shomate Equation)
Cp° = 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
Cp = heat capacity (J/mol*K)
H° = standard enthalpy (kJ/mol)
S° = standard entropy (J/mol*K)
t = temperature (K) / 1000.
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Temperature (K) | 298. to 1100. | 1100. to 6000. |
---|---|---|
A | 31.71409 | 32.88913 |
B | -13.69992 | 2.822116 |
C | 23.35567 | -0.478035 |
D | -9.008529 | 0.032464 |
E | -0.028758 | -3.174958 |
F | -45.57464 | -52.46318 |
G | 240.0428 | 230.8597 |
H | -36.44306 | -36.44306 |
Reference | Chase, 1998 | Chase, 1998 |
Comment | Data last reviewed in September, 1965 | Data last reviewed in September, 1965 |
Phase change data
Go To: Top, Gas phase thermochemistry data, Henry's Law data, Ion clustering 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
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Tfus | 186.1 | K | N/A | Dreisbach, 1955 | Uncertainty assigned by TRC = 0.02 K; TRC |
Tfus | 187.2 | K | N/A | Maass and Russell, 1918 | Uncertainty assigned by TRC = 1. K; TRC |
Tfus | 187.15 | K | N/A | Beckmann and Waentig, 1910 | Uncertainty assigned by TRC = 1.5 K; TRC |
Antoine Equation Parameters
log10(P) = A − (B / (T + C))
P = vapor pressure (bar)
T = temperature (K)
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Temperature (K) | A | B | C | Reference | Comment |
---|---|---|---|---|---|
134.3 to 206.7 | 4.02419 | 695.466 | -33.542 | Stull, 1947 | Coefficents calculated by NIST from author's data. |
206.7 to 343.8 | 4.15585 | 754.969 | -25.086 | Stull, 1947 | Coefficents calculated by NIST from author's data. |
Henry's Law data
Go To: Top, Gas phase thermochemistry data, Phase change data, Ion clustering 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 |
---|---|---|---|---|
0.72 | 6100. | C | N/A | missing citation refer to missing citation and missing citation but this value cannot be found there. |
25. | 650. | 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. |
1.3×10+9/KA | 10000. | 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. |
7.1×10+8/KA | 10000. | T | N/A |
Ion clustering data
Go To: Top, Gas phase thermochemistry data, 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 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° | 86.2 ± 8.4 | kJ/mol | TDAs | Caldwell and Kebarle, 1985 | gas phase; B,M |
ΔrH° | 73.2 | kJ/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° | 93.3 | J/mol*K | PHPMS | Caldwell and Kebarle, 1985 | gas phase; M |
ΔrS° | 92. | J/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° | 58. ± 11. | kJ/mol | TDAs | Caldwell and Kebarle, 1985 | gas phase; B |
Free energy of reaction
ΔrG° (kJ/mol) | T (K) | Method | Reference | Comment |
---|---|---|---|---|
39. | 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° | 46.0 | kJ/mol | PHPMS | Caldwell and Kebarle, 1985 | gas phase; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 71.1 | J/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° | 51.0 | kJ/mol | PHPMS | Caldwell and Kebarle, 1985 | gas phase; From thermochemical cycle,switching reaction(Br- HBr)SO2; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 80.3 | J/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° | 232. | kJ/mol | PHPMS | McMahon, Heinis, et al., 1988 | gas phase; switching reaction(CH3+)N2, Entropy change calculated or estimated, uses MCA(N2) = 202. kJ/mol; Foster, Williamson, et al., 1974; M |
By formula: HBr+ + HBr = (HBr+ • HBr)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 96. | kJ/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° | 67.4 ± 8.4 | kJ/mol | TDEq | Caldwell and Kebarle, 1985 | gas phase; B,M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 82.0 | J/mol*K | PHPMS | Caldwell and Kebarle, 1985 | gas phase; switching reaction(I-)SO2; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 43. ± 11. | kJ/mol | TDEq | Caldwell and Kebarle, 1985 | gas phase; B |
Free energy of reaction
ΔrG° (kJ/mol) | T (K) | Method | Reference | Comment |
---|---|---|---|---|
42.7 | 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° | 96. | J/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° | 73. ± 16. | kJ/mol | TDEq | Davidson, Fehsenfeld, et al., 1977 | gas phase; Anchored to HBr..Br- in Caldwell and Kebarle, 1985.; B |
Free energy of reaction
ΔrG° (kJ/mol) | T (K) | Method | Reference | Comment |
---|---|---|---|---|
53.1 | 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° | 66.9 | kJ/mol | FA | Davidson, Fehsenfeld, et al., 1977 | gas phase; switching reaction(NO3-)2HNO3; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 95.8 | J/mol*K | FA | Davidson, Fehsenfeld, et al., 1977 | gas phase; switching reaction(NO3-)2HNO3; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 38. | kJ/mol | FA | Davidson, Fehsenfeld, et al., 1977 | gas phase; switching reaction(NO3-)2HNO3; M |
References
Go To: Top, Gas phase thermochemistry data, Phase change data, Henry's Law data, Ion clustering data, 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]
Dreisbach, 1955
Dreisbach, R.R.,
Physical Properties of Chemical Compounds, Advances in Chemistry Series No. 15, Am. Chem. Soc.: Washington, D. C., 1955. [all data]
Maass and Russell, 1918
Maass, O.; Russell, J.,
Unsaturation and molecular compound formation,
J. Am. Chem. Soc., 1918, 40, 1561-1573. [all data]
Beckmann and Waentig, 1910
Beckmann, E.; Waentig, P.,
Cryoscopic Measurements at Low Temperatures,
Z. Anorg. Chem., 1910, 67, 17. [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]
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]
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]
Notes
Go To: Top, Gas phase thermochemistry data, Phase change data, Henry's Law data, Ion clustering data, References
- Symbols used in this document:
S°gas,1 bar Entropy of gas at standard conditions (1 bar) T 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 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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