Hydrobromic acid

Athanor · official

BrH · 80.91 g/mol

IUPAC name: bromane

Also called hydrogen bromide

Inorganic

Open in Athanor

Drawn from its SMILES with RDKit

DangerCauses severe skin burns and eye damage · May cause respiratory irritation

Names and identifiers

IUPAC name: bromane
Synonyms: hydrogen bromide, Hydrogen bromide, bromane
+ 36 more
Bromwasserstoff, Broomwaterstof, Bromowodor, Acido bromidrico, Acide bromhydrique, Hydrogen bromide (HBr), Anhydrous hydrobromic acid, Hydrogen bromide, anhydrous, Acido bromhidrico, Hydrogen monobromide, 3IY7CNP8XJ, Bromure d'hydrogene anhydre, Bromuro de hidrogeno anhidro, bromure d'hydrogene, CHEBI:47266, DTXSID0029713, NSC-606640, Hydrogenbromid, Anhydrous hydrogen bromide, bromidohydrogen, Acid, Hydrobromic, Bromide, Hydrogen, Hydrobromicum Acidum, Aqueous hydrogen bromide, RefChem:57367, Hydrogen bromide (HBr2), DTXCID809713, 233-113-0, MFCD00011323, Hydrobromic Acid, anyhydrous, SCHEMBL183, Hydrobromic Acid (47-48% in aqueous solution), HBR, Bromowodor [Polish], hydrogenbromide, Broomwaterstof [Dutch]
Molecular formula: BrH
Empirical formula: BrH
Molecular weight: 80.91 g/mol
Exact mass: 79.92616
CAS number: 10035-10-6
PubChem CID: 260
Canonical SMILES: Br
Isomeric SMILES: Br
InChI: InChI=1S/BrH/h1H
InChIKey: CPELXLSAUQHCOX-UHFFFAOYSA-N
Molfile

Names, InChI and the identifiers from PubChem, retrieved 2026-10-14.

Physical properties

TemperaturePressureDensity

Appearance: Colorless gas [Note: Shipped as a liquified compressed gas][6]
7 values
From Hazardous Substances Data Bank (HSDB), the most authoritative source here.
Value As written Source
– Hydrobromic acid, solution appears as a colorless to yellow aqueous solution with a pungent odor. Fumes irritate the eyes and mucous membranes. Corrosive to metals and tissue. [1] CAMEO Chemicals
– Hydrogen bromide, anhydrous appears as a colorless gas with a pungent irritating odor. Corrosive. Heavier than air. Prolonged exposure to fire or intense heat may result in the violent rupture and rocketing of the container. Long-term exposure to low concentrations or short-term exposure to high concentrations can result in adverse health effects from inhalation. Used to make other chemicals and as a catalyst in the manufacture of chemicals. Rate of onset: Immediate Persistence: Minutes to hours Odor threshold: 2 ppm Source/use/other hazard: Chemical manufacturing industry; very corrosive [1] CAMEO Chemicals
– Liquid; Gas Vapor [2] EPA Chemical Data Reporting (CDR)
– COLOURLESS COMPRESSED LIQUEFIED GAS WITH PUNGENT ODOUR. [3] ILO-WHO International Chemical Safety Cards (ICSCs)
– Colorless gas with a sharp, irritating odor. [4] Occupational Safety and Health Administration (OSHA)
– Colorless gas with a sharp, irritating odor. [Note: Shipped as a liquefied compressed gas. Often used in an aqueous solution.] [5] The National Institute for Occupational Safety and Health (NIOSH)
–shown Colorless gas [Note: Shipped as a liquified compressed gas] [6] Hazardous Substances Data Bank (HSDB)cites NIOSH. NIOSH Pocket Guide to Chemical Hazards. Department of Health & Human Services, Centers for Disease Control & Prevention. National Institute for Occupational Safety & Health. DHHS (NIOSH) Publication No. 2010-168 (2010). Available from: https://www.cdc.gov/niosh/npg
Odor: Sharp, irritating odor[6]
Melting point: -87 °C (-124 °F, NIOSH 2024)[1]
5 values
5 of 5 sources agree on it (most common value).
Value As written Source
−87 °Cshown -124 °F (NIOSH, 2024) [1] CAMEO Chemicals
−87 °C -87 °C [3] ILO-WHO International Chemical Safety Cards (ICSCs)
−87 °C -124 °F [4] Occupational Safety and Health Administration (OSHA)
−87 °C -87 °C [7] PAC Chemical Database, U.S. Department of Energy
−87 °C -124 °F [5] The National Institute for Occupational Safety and Health (NIOSH)
Boiling point: -66.5 °C @760 [mmHg][7]
5 values
5 of 5 sources agree on it (most common value).
Value As written Source
−66.8 °C -88.2 °F at 760 mmHg (USCG, 1999) [1] CAMEO Chemicalscites U.S. Coast Guard. 1999. Chemical Hazard Response Information System (CHRIS) - Hazardous Chemical Data. Commandant Instruction 16465.12C. Washington, D.C.: U.S. Government Printing Office.
−67 °C -67 °C [3] ILO-WHO International Chemical Safety Cards (ICSCs)
−66.8 °C -88.2 °F [4] Occupational Safety and Health Administration (OSHA)
−66.5 °Cshown -66.5 °C @760 [mm Hg] [7] PAC Chemical Database, U.S. Department of Energy
−67 °C -88 °F [5] The National Institute for Occupational Safety and Health (NIOSH)
Density: 3.31 g/L[7]
5 values
Only one source reports it.
Value As written Source
– 2.14 at -88.6 °F (USCG, 1999) - Denser than water [1] CAMEO Chemicalscites U.S. Coast Guard. 1999. Chemical Hazard Response Information System (CHRIS) - Hazardous Chemical Data. Commandant Instruction 16465.12C. Washington, D.C.: U.S. Government Printing Office.
– Relative density (water = 1): 1.8 [3] ILO-WHO International Chemical Safety Cards (ICSCs)
– 2.14 at -88.6 °F [4] Occupational Safety and Health Administration (OSHA)
0.00331 g/mLshown 3.31 g/L [7] PAC Chemical Database, U.S. Department of Energy
– 2.81(relative gas density) [5] The National Institute for Occupational Safety and Health (NIOSH)
Solubility in water: Solubility in water, g/100ml at 20 °C: 193[3]
4 values
From ILO-WHO International Chemical Safety Cards (ICSCs), the most authoritative source here.
Value As written Source
– 49 % (NIOSH, 2024) [1] CAMEO Chemicals
– For more Solubility (Complete) data for Hydrogen bromide (6 total), please visit the HSDB record page. [6] Hazardous Substances Data Bank (HSDB)
–shown Solubility in water, g/100ml at 20 °C: 193 [3] ILO-WHO International Chemical Safety Cards (ICSCs)
– 49% [5] The National Institute for Occupational Safety and Health (NIOSH)
Vapor pressure: 18,410 mmHg at 25 °C[6]
3 values
3 of 3 sources agree on it (most common value).
Value As written Source
18410 mmHgshown 18,410 mm Hg at 25 °C [6] Hazardous Substances Data Bank (HSDB)cites Daubert, T.E., R.P. Danner. Physical and Thermodynamic Properties of Pure Chemicals Data Compilation. Washington, D.C.: Taylor and Francis, 1989.
18000 mmHg Vapor pressure, kPa at 20 °C: 2445 [3] ILO-WHO International Chemical Safety Cards (ICSCs)
18410 mmHg 18410 [mm Hg] @25 °C [7] PAC Chemical Database, U.S. Department of Energy
3 more values were reported but failed the checks (unreadable or out of range), so they are not shown.

Value	As written	Source
–	Hydrobromic acid, solution appears as a colorless to yellow aqueous solution with a pungent odor. Fumes irritate the eyes and mucous membranes. Corrosive to metals and tissue.	[1] CAMEO Chemicals
–	Hydrogen bromide, anhydrous appears as a colorless gas with a pungent irritating odor. Corrosive. Heavier than air. Prolonged exposure to fire or intense heat may result in the violent rupture and rocketing of the container. Long-term exposure to low concentrations or short-term exposure to high concentrations can result in adverse health effects from inhalation. Used to make other chemicals and as a catalyst in the manufacture of chemicals. Rate of onset: Immediate Persistence: Minutes to hours Odor threshold: 2 ppm Source/use/other hazard: Chemical manufacturing industry; very corrosive	[1] CAMEO Chemicals
–	Liquid; Gas Vapor	[2] EPA Chemical Data Reporting (CDR)
–	COLOURLESS COMPRESSED LIQUEFIED GAS WITH PUNGENT ODOUR.	[3] ILO-WHO International Chemical Safety Cards (ICSCs)
–	Colorless gas with a sharp, irritating odor.	[4] Occupational Safety and Health Administration (OSHA)
–	Colorless gas with a sharp, irritating odor. [Note: Shipped as a liquefied compressed gas. Often used in an aqueous solution.]	[5] The National Institute for Occupational Safety and Health (NIOSH)
–shown	Colorless gas [Note: Shipped as a liquified compressed gas]	[6] Hazardous Substances Data Bank (HSDB)cites NIOSH. NIOSH Pocket Guide to Chemical Hazards. Department of Health & Human Services, Centers for Disease Control & Prevention. National Institute for Occupational Safety & Health. DHHS (NIOSH) Publication No. 2010-168 (2010). Available from: https://www.cdc.gov/niosh/npg

Value	As written	Source
−87 °Cshown	-124 °F (NIOSH, 2024)	[1] CAMEO Chemicals
−87 °C	-87 °C	[3] ILO-WHO International Chemical Safety Cards (ICSCs)
−87 °C	-124 °F	[4] Occupational Safety and Health Administration (OSHA)
−87 °C	-87 °C	[7] PAC Chemical Database, U.S. Department of Energy
−87 °C	-124 °F	[5] The National Institute for Occupational Safety and Health (NIOSH)

Value	As written	Source
−66.8 °C	-88.2 °F at 760 mmHg (USCG, 1999)	[1] CAMEO Chemicalscites U.S. Coast Guard. 1999. Chemical Hazard Response Information System (CHRIS) - Hazardous Chemical Data. Commandant Instruction 16465.12C. Washington, D.C.: U.S. Government Printing Office.
−67 °C	-67 °C	[3] ILO-WHO International Chemical Safety Cards (ICSCs)
−66.8 °C	-88.2 °F	[4] Occupational Safety and Health Administration (OSHA)
−66.5 °Cshown	-66.5 °C @760 [mm Hg]	[7] PAC Chemical Database, U.S. Department of Energy
−67 °C	-88 °F	[5] The National Institute for Occupational Safety and Health (NIOSH)

Value	As written	Source
–	2.14 at -88.6 °F (USCG, 1999) - Denser than water	[1] CAMEO Chemicalscites U.S. Coast Guard. 1999. Chemical Hazard Response Information System (CHRIS) - Hazardous Chemical Data. Commandant Instruction 16465.12C. Washington, D.C.: U.S. Government Printing Office.
–	Relative density (water = 1): 1.8	[3] ILO-WHO International Chemical Safety Cards (ICSCs)
–	2.14 at -88.6 °F	[4] Occupational Safety and Health Administration (OSHA)
0.00331 g/mLshown	3.31 g/L	[7] PAC Chemical Database, U.S. Department of Energy
–	2.81(relative gas density)	[5] The National Institute for Occupational Safety and Health (NIOSH)

Value	As written	Source
–	49 % (NIOSH, 2024)	[1] CAMEO Chemicals
–	For more Solubility (Complete) data for Hydrogen bromide (6 total), please visit the HSDB record page.	[6] Hazardous Substances Data Bank (HSDB)
–shown	Solubility in water, g/100ml at 20 °C: 193	[3] ILO-WHO International Chemical Safety Cards (ICSCs)
–	49%	[5] The National Institute for Occupational Safety and Health (NIOSH)

Value	As written	Source
18410 mmHgshown	18,410 mm Hg at 25 °C	[6] Hazardous Substances Data Bank (HSDB)cites Daubert, T.E., R.P. Danner. Physical and Thermodynamic Properties of Pure Chemicals Data Compilation. Washington, D.C.: Taylor and Francis, 1989.
18000 mmHg	Vapor pressure, kPa at 20 °C: 2445	[3] ILO-WHO International Chemical Safety Cards (ICSCs)
18410 mmHg	18410 [mm Hg] @25 °C	[7] PAC Chemical Database, U.S. Department of Energy

Each value as its source reports it, with the source's number after it (listed under References). Where several sources report a property, the row shows the value most of them agree on, the rule the app uses; open the values to see every one.

Calculated

Heavy atoms: 1
Rings: 0
Aromatic rings: 0
Fraction sp³ carbons (Fsp3): 0
H-bond donors: 0 computed here · PubChem 1
H-bond acceptors: 0
Rotatable bonds: 0
TPSA (Å²): 0
Formal charge: 0
XLogP3: 1 PubChem
Complexity: 0 PubChem
Stereocenters: None
Double-bond geometry: None specified
Point group: C∞v of one 3D conformer with its hydrogens, by Athanor’s engine (as in the app)

Elemental analysis

H1.25%
Br98.75%

Isotope pattern

Each peak is a nominal mass with its abundance-weighted exact mass, as a percentage of the tallest, from IUPAC natural isotope abundances.

Computed from the structure with RDKit 2026.09 when this page was built, beside PubChem's own computed values from its record; where the two differ, both are shown.

Predicted

log P: 0.58 Crippen (Wildman and Crippen 1999)
log S (water solubility): -0.71 ESOL (Delaney 2004), log mol/L
Synthetic accessibility: 6.96 SA score, 1 easy to 10 hard (Ertl and Schuffenhauer 2009)

Drug-likeness: Lipinski’s rule of five

Molecular weight ≤ 500: 80.91
log P ≤ 5 (Crippen): 0.58
H-bond donors ≤ 5: 0
H-bond acceptors ≤ 10: 0

Passes all four rules.

Predictions, not measurements; each names its method. A measured log P, where a source reports one, is under Physical properties.

Safety

Danger

Harmonized EU classification (CLP Annex VI). Source [8].

Compressed gas
Corrosive
Harmful or irritant

H314Causes severe skin burns and eye damage
H335May cause respiratory irritation

Precautionary statements: P260, P261, P264, P271, P280, P301+P330+P331, P302+P361+P354, P304+P340, P305+P354+P338, P316, P319, P321, P363, P403+P233, P405, P501

View all classifications (4)

[8] Regulation (EC) No 1272/2008 of the European Parliament and of the Council · DangerH314, H335
[9] European Chemicals Agency (ECHA)This chemical does not meet GHS hazard criteria for 0.2% (1 of 432) of reports.
[9] European Chemicals Agency (ECHA) · 432 reports · DangerH280, H314, H318, H331, H335
[6] Hazardous Substances Data Bank (HSDB) · DangerH280, H314, H318, H331, H335

Exposure limits

PEL-TWA (8-Hour Time Weighted Average): 3 ppm (10 mg/m³)[4]
PEL: TWA 3 ppm (10 mg/m3) See Appendix G[5]
REL: C 3 ppm (10 mg/m3)[5]
TLV: 2 ppm as STEL.[3]
TLV-C (Ceiling): 2 ppm [2001][4]
IDLH: 30 ppm [From npg: Hydrogen bromide] (NIOSH, 2024)[1]

First aid

Excerpt from ERG Guide 154 [Substances - Toxic and/or Corrosive (Non-Combustible)]: Refer to the "General First Aid" section. Specific First Aid: For corrosives, in case of contact, immediately flush skin or eyes with running water for at least 30 minutes. Additional flushing may be required. (ERG, 2024)[1]
Excerpt from NIOSH Pocket Guide for Hydrogen bromide: Eye: â¢ irrigate immediately (solution) - If this chemical in solution contacts the eyes, immediately wash (irrigate) the eyes with large amounts of water, occasionally lifting the lower and upper lids. Get medical attention immediately. â¢ frostbite - If eye tissue is frozen, seek medical attention immediately; if tissue is not frozen, immediately and thoroughly flush the eyes with large amounts of water for at least 15 minutes, occasionally lifting the lower and upper eyelids.[1]
General First Aid: · Call 911 or emergency medical service. · Ensure that medical personnel are aware of the material(s) involved, take precautions to protect themselves and avoid contamination. · Move victim to fresh air if it can be done safely. · Administer oxygen if breathing is difficult. · If victim is not breathing: -- DO NOT perform mouth-to-mouth resuscitation; the victim may have ingested or inhaled the substance. -- If equipped and pulse detected, wash face and mouth, then give artificial respiration using a proper respiratory medical device (bag-valve mask, pocket mask equipped…[10]
General First Aid: · Call 911 or emergency medical service. · Ensure that medical personnel are aware of the material(s) involved, take precautions to protect themselves and avoid contamination. · Move victim to fresh air if it can be done safely. · Administer oxygen if breathing is difficult. · If victim is not breathing: -- DO NOT perform mouth-to-mouth resuscitation; the victim may have ingested or inhaled the substance. -- If equipped and pulse detected, wash face and mouth, then give artificial respiration using a proper respiratory medical device (bag-valve mask, pocket mask equipped…[10]

Storage

Separated from incompatible materials. See Chemical Dangers. Cool. Dry. Ventilation along the floor.[3]
Separated from incompatible materials. ... Cool. Dry. Ventilation along the floor.[6]
Keep container tightly closed in a dry and well-ventilated place. Containers which are opened must be carefully resealed and kept upright to prevent leakage.[6]
Store in a cool, dry, well-ventilated location. Separate from alkalies, oxidizing materials, amines, halogens, and metals. (hydrobromic acid solution)[6]

Incompatibilities

Incompatible materials: Strong oxidizing agents, Strong bases, Ammonia, Ozone, Halogens, Amines, Gives off hydrogen by reaction with metals.[6]
The aqueous solution is a strong acid. Violent reaction with strong oxidizers, strong caustics, and many organic compounds causing fire and explosion hazard. Reacts with water forming hydrobromic acid. Incompatible with aliphatic amines, alkanolamines, alkylene oxides, aromatic amines, amides, ammonia, ammonium hydroxide, calcium oxide, epichlorohydrin, fluorine, isocyanates, oleum, organic anhydrides, sulfuric acid, sodium tetrahydroborate, vinyl acetate. Hydrobromic acid is highly corrosive to most metals forming flammable hydrogen.[6]
The reaction of fluorine with gaseous or aqueous hydrobromic acid is accompanied by flame.[6]
Reacts violently with F2, FE2O3, HN3, O3.[6]

Safety data sheets on the supplier’s page: Thermo Fisher Scientific, Sinfoo Biotech, abcr GmbH.

Always read the supplier’s safety data sheet before working with it.

Spectra

GC-MSNIST Mass Spectrometry Data Center · NIST Mass Spectrometry Data Center · SpectraBase

Experimental spectra held by these sources; each link opens the source's own record.

Literature

Reading PubChem, OpenAlex and GSRS…

Bioactivity

Reading ChEMBL…

References

[1]CAMEO Chemicals · Public domain (NOAA) · via PubChem · retrieved 2026-10-14
[2]EPA Chemical Data Reporting (CDR) · Public domain (US EPA) · via PubChem · retrieved 2026-10-14
[3]ILO-WHO International Chemical Safety Cards (ICSCs) · CC BY 4.0 · via PubChem · retrieved 2026-10-14
[4]Occupational Safety and Health Administration (OSHA) · Public domain (US DOL) · via PubChem · retrieved 2026-10-14
[5]The National Institute for Occupational Safety and Health (NIOSH) · Public domain (US CDC) · via PubChem · retrieved 2026-10-14
[6]Hazardous Substances Data Bank (HSDB) · Public domain (US NLM) · via PubChem · retrieved 2026-10-14
[7]PAC Chemical Database, U.S. Department of Energy · Public domain (US DOE) · via PubChem · retrieved 2026-10-14
[8]Regulation (EC) No 1272/2008 of the European Parliament and of the Council · EU reuse policy, CC BY 4.0 · via PubChem · retrieved 2026-10-14
[9]European Chemicals Agency (ECHA) · ECHA legal notice: reuse with acknowledgement · via PubChem · retrieved 2026-10-14
[10]Emergency Response Guidebook (ERG) · Public domain (US DOT) · via PubChem · retrieved 2026-10-14
[11]NIST Mass Spectrometry Data Center · Linked only · via PubChem · retrieved 2026-10-14
[12]SpectraBase · Linked only · via PubChem · retrieved 2026-10-14
·Calculated values: computed by Athanor with RDKit 2026.09 from the structure.
·Literature on PubChem

Data last updated 2026-10-14.