He Hydrobromic acid Is formed when the hydrogen bromide gas dissolves in water. Hydrobromic acid (its aqueous form) and hydrogen bromide (its gaseous or anhydrous form) are interconvertible. Its anhydrous form is a molecule made up of a bromine atom (Br) and a hydrogen atom (H).
Of the known mineral acids, hydrobromic acid is one of the strongest. It is transported in the form of liquefied compressed gas. It is often used as an aqueous solution. The aqueous acid is commercially available as 48% and 62% colorless solutions.
Inhalation, ingestion or skin contact with the substance can cause serious injury or death.
- Formulas : HBr or BrH
- CAS number : 10035-10-6
- WILDEBEEST : 1788 (hydrobromic acid)
- WILDEBEEST : 1048 (hydrogen bromide)
2D structure
3D structure
characteristics
Physical and chemical properties
| Molecular weight: | 80.912 g / mol |
| Boiling point: | -67 ° C |
| Melting point: | -87 ° C |
| Relative density (water = 1): | 1.8 |
| Solubility in water, g / 100 ml at 20 ° C: | 193 |
| Vapor pressure, kPa at 20 ° C: | 2445 |
| Relative vapor density (air = 1): | 2.8 |
- Hydrobromic acid belongs to the group of strong non-oxidizing acids (together with hydrochloric acid and hydroiodic acid). These acids provide anions that do not act as oxidants.
- They have a pKa value of less than -2, or a pH value of less than 2.
- In its aqueous form (hydrobromic acid), it is a solution between colorless and yellow.
- It has an acrid smell.
- It is corrosive to metals and tissues.
- In its anhydrous form (hydrogen bromide), it is a colorless gas.
- It has a sharp and irritating odor.
- It is heavier than air.
- It is very corrosive.
- Prolonged exposure to fire or severe heat may result in the violent rupture and rupture of your container.
- Inflammability
- Strong non-oxidizing acids are generally non-flammable.
- Hydrobromic acid is not combustible on its own, but can decompose on heating, producing corrosive and / or toxic fumes that are dispersed through the air.
- Some of these fumes are oxidizing and can ignite fuels (such as wood, paper, oil, clothing, etc.).
- Contact with metals may produce hydrogen gas (flammable).
- Containers may explode when heated.
- Hydrogen bromide is also not flammable, but in case of fire, the pressure vessel containing it may explode, releasing toxic and irritating vapors.
Reactivity
- Strong non-oxidizing acids are generally soluble in water with the release of hydrogen ions. The resulting solutions have a pH of 1 or close to 1.
- Acids neutralize chemical bases (eg, amines and inorganic hydroxides) forming salts, and dangerously large amounts of heat can be generated in small spaces.
- Dissolving acids in water (or further dilution of their concentrated solutions) can generate enough heat to cause some of the water to boil explosively, producing dangerous acid splashes.
- These materials react with active metals, including structural metals such as aluminum and iron, releasing hydrogen (flammable gas).
- They also release hydrogen cyanide gas by reacting with cyanide compounds.
- They generate flammable and / or toxic gases upon contact with strong dithiocarbamates, isocyanates, mercaptans, nitrides, nitriles, sulfides and reducing agents.
- Hydrobromic acid and hydrogen bromide have known catalytic activity.
- The hydrobromic acid reacts exothermically with chemical bases (for example: amines and inorganic hydroxides) forming salts. Reactions can generate a lot of heat, which is dangerous in small spaces.
- Dissolution in water (or dilution of concentrated solutions with water) can also generate significant heat.
- Reacts with sodium hypochlorite, producing toxic gases.
- It reacts with active metals (including iron and aluminum) and also with many less active metals, dissolving the metal and releasing hydrogen and / or toxic gases.
- Reacts with cyanide salts and their compounds, releasing gaseous hydrogen cyanide.
- By reacting with certain alkenes (such as allyl chloride), violent polymerization can be generated.
- It also reacts with weak or strong dithiocarbamates, isocyanates, mercaptans, nitrides, nitriles, sulfides and reducing agents, generating flammable and / or toxic gases.
- Reacts with sulfites, nitrites, thiosulfates (hydrogen sulfide gases, H2S, and sulfur trioxide, SO3), dithionites (generating sulfur dioxide gas, SO2) and carbonates (generating carbon dioxide gas, which is non-toxic , But the heat and the splash of the reaction that can be dangerous).
- It is incompatible with ozone and fluorine.
- Hydrogen bromide fumes in moist air form clouds containing hydrobromic acid.
- Hydrogen bromide is a strong anhydrous acid (without water).
- Reacts quickly and exothermically with bases of all kinds (including amines and amides).
- Reacts exothermically with carbonates (including limestone and building materials containing limestone) and hydrogen carbonates, generating carbon dioxide.
- Reacts with sulfides, carbides, borides and phosphides generating toxic or flammable gases.
- Reacts with many metals (including aluminum, zinc, calcium, magnesium, iron, tin and all alkali metals) generating hydrogen gas (flammable).
- Reacts violently with acetic anhydride, 2-aminoethanol, ammonium hydroxide, calcium phosphide, chlorosulfonic acid, 1,1-difluoroethylene, ethylenediamine, ethyleneimine, oleum, perchloric acid, b-propiolactone, propylene oxide, silver perchlorate Carbon tetrachloride, uranium (IV) phosphate, vinyl acetate, calcium carbide, rubidium carbide, cesium acetylide, rubidium acetylide, magnesium boride, mercury (II) sulfate, calcium phosphide, calcium carbide .
Toxicity
- Hydrobromic acid and hydrogen bromide are toxic.
- Hydrobromic acid is corrosive to metals and fabrics.
- Its vapors irritate the eyes and mucous membranes.
- Inhalation, ingestion or skin contact with the substance can cause serious injury or death.
- Contact with the solution may cause severe burns to the skin and eyes.
- Prolonged exposure to low concentrations (or short-term exposure to high concentrations) may result in adverse health effects through inhalation.
- The effects of contact or inhalation may be delayed.
- Fire may produce irritating, corrosive and / or toxic gases.
- Runoff from fire control or dilution water can be corrosive and / or toxic and cause contamination.
- Inhalation of hydrogen bromide causes severe irritation of the nose and upper respiratory tract and lung injury.
- Ingestion causes burns to the mouth and stomach.
- Contact with eyes causes severe irritation and burns.
- Contact with skin causes irritation and burns.
Applications
- Hydrobromic acid is used as a substrate and as a catalyst in the manufacture of chemicals.
- It is an indispensable raw material in the manufacture of organic intermediates, inorganic pharmaceuticals, photosensitive materials, dyes and medicines.
- It is also used in the production of bromine compounds.
- It is used as an important agent in the industrial processes of the reactions of isomerization, polymerization, hydration and dehydration and esterification.
- It plays an essential role for the extraction of mercury from cinnabar ore.
- In the past, bromides were widely used as sedatives and antiepileptic agents, and are still used as sedatives in some areas of the world.
- It is still found as a bromide salt in many medications.
- The main source of bromide exposure in humans in the United States is the presence of bromide residues in food.
- Fumigants containing bromine are widely used in horticulture and post harvest treatments, however the amounts are usually too low to cause toxicity.
- Contaminated well water can also be a source of exposure to bromide.
Clinical Effects
Bromide poisoning is rare and, when it does occur, it is usually secondary to chronic ingestion rather than an acute overdose.
Acute exposure
The effects of acute ingestion may include nausea, vomiting, gastric irritation, CNS depression , Coma, hypotension, tachycardia, and respiratory distress.
Chronic exposure
Ingestion of chronic and excessive amounts can produce a toxic syndrome called"bromismo", which is characterized by behavioral changes, Hallucinations , psychosis , ataxia , Irritability, headache And confusion.
Other symptoms of chronic bromide poisoning include: anorexy , Weight loss, constipation, Speech abnormality , anemia , Bromoderma (erythematous, nodular or acneiform eruption on the face and possibly the whole body), bleeding or pustular eruptions on the skin, necrolysis, musculoskeletal pain, lethargy and enzymatic alterations in the liver.
Safety and Risks
The Globally Harmonized System of Classification and Labeling of Chemicals (GHS) is an internationally agreed system, created by the United Nations and designed to replace the various classification and labeling standards used in different countries through the use of globally consistent criteria.
Hazard classes (and their corresponding GHS chapter), classification and labeling standards, and recommendations for hydrobromic acid are as follows (European Chemicals Agency, 2017, United Nations, 2015, PubChem, 2017):
(United Nations, 2015, p.345)
(United Nations, 2015, p.381)
(United Nations, 2015, p.378).
(United Nations, 2015, p.395).
References
- Anon, (2006). Hydrogen-bromide-3D-vdW [image] Retrieved from wikipedia.org.
- Anon, (2007). Water-3D-vdW [image] Retrieved from wikipedia.org.
- European Chemicals Agency (ECHA). (2017). Summary of Classification and Labeling.
- Annex VI of Regulation (EC) No 1272/2008 (CLP Regulation). Hydrogen bromide. Recovered on January 16, 2017.
- Hazardous Substances Data Bank (HSDB). TOXNET. (2017). Hydrogen bromide. Bethesda, MD, US: National Library of Medicine.
- National Institute of Occupational Safety (INSHT). (2010). International Chemical Safety Cards. Hydrogen bromide (liquefied). Ministry of Employment and Security. Madrid. IS; Recovered from insth.es.
- United Nations (2015). Globally Harmonized System of Classification and Labeling of Chemicals (SGA) Sixth Revised Edition. New York, USA: United Nations publication. Retrieved from unece.org.
- National Center for Biotechnology Information. PubChem Compound Database. (2017). Hydrobromic acid. HI. Bethesda, MD, US: National Library of Medicine.
- National Oceanic and Atmospheric Administration (NOAA). CAMEO Chemicals. (2017). Chemical Datasheet. Acids, Strong Non-oxidizing. Silver Spring, MD. EU;
- National Oceanic and Atmospheric Administration (NOAA). CAMEO Chemicals. (2017). Chemical Datasheet. Hydrobromic acid. Silver Spring, MD. EU
- National Oceanic and Atmospheric Administration (NOAA). CAMEO Chemicals. (2017). Chemical Datasheet. Hydrogen bromide, anhydrous. Silver Spring, MD. EU
- Wikipedia. (2017). Hydrobromic acid. Retrieved January 17, 2017, from wikipedia.org.
- Wikipedia. (2017). Hydrogen bromide. Retrieved January 17, 2017, from wikipedia.org.
- Yoffe, D., Frim, R., Ukeles, S.D., Dagani, M.J., Barda, H.J., Benya, T. J., & Sanders, D.C. (2000). Bromine Compounds. In Ullmann's Encyclopedia of Industrial Chemistry. Wiley-VCH Verlag GmbH & Co. KGaA.