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What is Hydrobromic Acid?

Angie Bates
Angie Bates

Hydrobromic acid is a type of clear or yellowish liquid containing hydrogen bromide and water. This acid is stable under normal conditions and often used in industry to make isomers and polymers, as well as for hydration reactions. It is also used in laboratories for scientific experiments. Generally, hydrobromic acid is refereed to as hydrogen bromide, or HBr, by those working with it.

A hydrogen bromide molecule consists of an atom of hydrogen attached to an atom of bromine, both elements found on the periodic table. It generally exists as a gas but can be completely dissolved in water to create an acid, or a substances with a pH (parts Hydrogen) less than seven. The stronger the acid the more corrosive and dangerous the substance. Acids may be used to neutralize bases, or substances with a pH greater than 7. Hydrobromic acid has a melting point much lower than water's, 14°F (-10°C), and its boiling point is higher, 251.6°F (122°C).

The Periodic Table of Elements.
The Periodic Table of Elements.

Hydrobromic acid is used in isomerization, or a chemical reaction which causes the structure of molecules to change without changing their molecular composition, and polymerization, or a reaction which links together strands of molecules in long chains. Isomerization is particularly important for substances like fuels, which evidence suggests burn better with a bent molecular structure rather than a straight. Polymerization is seen most frequently in the creation of plastics. Additionally, hydrobromic acid can be used in hydration reactions to create certain alcohols.

Working with a fume hood is necessary when using hydrobromic acid in a lab setting.
Working with a fume hood is necessary when using hydrobromic acid in a lab setting.

This acid's main use, however, is to produce inorganic bromides. Inorganic bromides may be found in medicine, disinfectants, and may be used in the oil industry. They are also frequently used in various pesticides. A commercially made product, this acid normally comes in drums and should be stored in cool, dry places out of the sun and near nothing that might act as a oxidizing agent, causing a reaction. The liquid will darken if it is exposed to light.

A strong acid, hydrobromic acid smells pungent and can irritate the nose and lungs if inhaled, and may cause burning and shortness of breath. Prolonged exposure may cause respiratory discharge. Also, it can cause irritation — or even burns — to skin if touched, and prolonged exposure might result in a skin condition called dermatitis. It is poisonous if ingested. Safety glasses and gloves should always be worn when working with the substance, and good ventilation, particularly the use a fume hood when working in a laboratory, is also important.

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    • The Periodic Table of Elements.
      By: jelena zaric
      The Periodic Table of Elements.
    • Working with a fume hood is necessary when using hydrobromic acid in a lab setting.
      By: Massachusetts Dept. of Environmental Protection
      Working with a fume hood is necessary when using hydrobromic acid in a lab setting.