Barium bromide is the chemical compound with the

formula In science, a formula is a concise way of expressing information symbolically, as in a mathematical formula or a ''chemical formula''. The informal use of the term ''formula'' in science refers to the general construct of a relationship betwee ...

BaBr₂. It is ionic in nature.

Structure and properties

BaBr₂ crystallizes in the lead chloride ( cotunnite) motif, giving white

orthorhombic In crystallography, the orthorhombic crystal system is one of the 7 crystal systems. Orthorhombic lattices result from stretching a cubic lattice along two of its orthogonal pairs by two different factors, resulting in a rectangular prism with a r ...

crystals that are deliquescent. In aqueous solution BaBr₂ behaves as a simple salt. Solutions of barium bromide reacts with the sulfate salts to produce a solid precipitate of

barium sulfate Barium sulfate (or sulphate) is the inorganic compound with the chemical formula Ba SO4. It is a white crystalline solid that is odorless and insoluble in water. It occurs as the mineral barite, which is the main commercial source of barium an ...

. :BaBr₂ + → BaSO₄ + 2 Br⁻ Similar reactions occur with

oxalic acid Oxalic acid is an organic acid with the systematic name ethanedioic acid and formula . It is the simplest dicarboxylic acid. It is a white crystalline solid that forms a colorless solution in water. Its name comes from the fact that early inve ...

hydrofluoric acid Hydrofluoric acid is a Solution (chemistry), solution of hydrogen fluoride (HF) in water. Solutions of HF are colourless, acidic and highly Corrosive substance, corrosive. It is used to make most fluorine-containing compounds; examples include th ...

, and phosphoric acid, giving solid precipitates of

barium oxalate Barium oxalate (BaC2O4), a barium salt of oxalic acid, is a white odorless powder that is sometimes used as a green pyrotechnic colorant generally in specialized pyrotechnic compositions containing magnesium metal powder. Flame color is rich and vi ...

, fluoride, and phosphate, respectively.

Preparation

Barium bromide can be prepared by treating barium sulfide or barium carbonate with hydrobromic acid: :BaS + 2 HBr → BaBr₂ + H₂S :BaCO₃ + 2 HBr → BaBr₂ + CO₂ + H₂O Barium bromide crystallizes from concentrated aqueous solution in its di

hydrate In chemistry, a hydrate is a substance that contains water or its constituent elements. The chemical state of the water varies widely between different classes of hydrates, some of which were so labeled before their chemical structure was understo ...

, BaBr₂·2H₂O. Heating this dihydrate to 120 °C gives the

anhydrous A substance is anhydrous if it contains no water. Many processes in chemistry can be impeded by the presence of water; therefore, it is important that water-free reagents and techniques are used. In practice, however, it is very difficult to achie ...

salt.

Uses

Barium bromide is a precursor to chemicals used in photography and to other bromides.
Historically, barium bromide was used to purify radium in a process of

fractional crystallization Fractional crystallization may refer to: * Fractional crystallization (chemistry), a process to separate different solutes from a solution * Fractional crystallization (geology) Fractional crystallization, or crystal fractionation, is one of the ...

devised by Marie Curie. Since radium precipitates preferentially in a solution of barium bromide, the ratio of radium to barium in the precipitate would be higher than the ratio in the solution.

Safety

Barium bromide, along with other water-soluble barium salts(like barium chloride), is toxic. However, there is no conclusive data available on its hazards. https://www.sigmaaldrich.com/MSDS/MSDS/DisplayMSDSPage.do?country=US&language=en&productNumber=413607&brand=ALDRICH ,

In popular culture

The compound appears in the intro title card of

Breaking Bad ''Breaking Bad'' is an American crime drama television series created and produced by Vince Gilligan. Set and filmed in Albuquerque, New Mexico, the series follows Walter White (Bryan Cranston), an underpaid, overqualified, and dispirited hig ...

, where the title is replaced with "Br" and "Ba", the symbols of bromine and

barium Barium is a chemical element with the symbol Ba and atomic number 56. It is the fifth element in group 2 and is a soft, silvery alkaline earth metal. Because of its high chemical reactivity, barium is never found in nature as a free element. Th ...

, respectively.

References

{{Authority control Bromides Alkaline earth metal halides Barium compounds