Barium chloride

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Barium chloride
Cotunnite structure.png
Barium chloride.jpg
Other names
Barium muriate
Muryate of Barytes [1]
Barium dichloride crystals
Neutral barium chloride
3D model (JSmol)
ECHA InfoCard 100.030.704 OOjs UI icon edit-ltr-progressive.svg
EC Number
  • 233-788-1
PubChem CID
RTECS number
  • CQ8750000 (anhydrous)
    CQ8751000 (dihydrate)
UN number 1564
  • InChI=1S/Ba.2ClH/h;2*1H/q+2;;/p-2 Yes check.svgY
  • InChI=1/Ba.2ClH/h;2*1H/q+2;;/p-2
  • [Ba+2].[Cl-].[Cl-]
Molar mass 208.23 g/mol (anhydrous)
244.26 g/mol (dihydrate)
AppearanceWhite solid
Odor Odourless
Density 3.856 g/cm3 (anhydrous)
3.0979 g/cm3 (dihydrate)
Melting point 962 °C (1,764 °F; 1,235 K)(960 °C, dihydrate)
Boiling point 1,560 °C (2,840 °F; 1,830 K)
31.2 g/100 mL (0 °C)
35.8 g/100 mL (20 °C)
59.4 g/100 mL (100 °C)
Solubility soluble in methanol, insoluble in ethanol, ethyl acetate [2]
−72.6×10−6 cm3/mol
orthogonal (anhydrous)
monoclinic (dihydrate)
123.9 J/(k mol)
858.56 kJ/mol
Occupational safety and health (OHS/OSH):
Main hazards
Highly toxic, corrosive
GHS labelling:
H301, H302, H332
P261, P264, P270, P271, P301+P310, P304+P312, P304+P340, P312, P321, P330, P405, P501
NFPA 704 (fire diamond)
Flash point Non-flammable
Lethal dose or concentration (LD, LC):
78 mg/kg (rat, oral)
50 mg/kg (guinea pig, oral) [3]
112 mg Ba/kg (rabbit, oral)
59 mg Ba/kg (dog, oral)
46 mg Ba/kg (mouse, oral) [3]
NIOSH (US health exposure limits):
PEL (Permissible)
TWA 0.5 mg/m3 [4]
REL (Recommended)
TWA 0.5 mg/m3 [4]
IDLH (Immediate danger)
50 mg/m3 [4]
Safety data sheet (SDS) NIH BaCl
Related compounds
Other anions
Barium fluoride
Barium bromide
Barium iodide
Other cations
Beryllium chloride
Magnesium chloride
Calcium chloride
Strontium chloride
Radium chloride
Lead chloride
Supplementary data page
Barium chloride (data page)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Barium chloride is an inorganic compound with the formula Ba Cl2. It is one of the most common water-soluble salts of barium. Like most other water-soluble barium salts, it is white, highly toxic, and imparts a yellow-green coloration to a flame. It is also hygroscopic, converting first to the dihydrate BaCl2(H2O)2. It has limited use in the laboratory and industry. [5]


Structure and properties

BaCl2 crystallizes in two forms (polymorphs). One form has the cubic fluorite (CaF2) structure and the other the orthorhombic cotunnite (PbCl2) structure. Both polymorphs accommodate the preference of the large Ba2+ ion for coordination numbers greater than six. [6] The coordination of Ba2+ is 8 in the fluorite structure [7] and 9 in the cotunnite structure. [8] When cotunnite-structure BaCl2 is subjected to pressures of 7–10 GPa, it transforms to a third structure, a monoclinic post-cotunnite phase. The coordination number of Ba2+ increases from 9 to 10. [9]

In aqueous solution BaCl2 behaves as a simple salt; in water it is a 1:2 electrolyte and the solution exhibits a neutral pH. Its solutions react with sulfate ion to produce a thick white precipitate of barium sulfate.

Ba2+ + SO2−
→ BaSO4

Oxalate effects a similar reaction:

Ba2+ + C

When it is mixed with sodium hydroxide, it gives the dihydroxide, which is moderately soluble in water.


On an industrial scale, it is prepared via a two step process from barite (barium sulfate): [10]

BaSO4 + 4 C → BaS + 4 CO

This first step requires high temperatures.

BaS + 2 HCl → BaCl2 + H2S

In place of HCl, chlorine can be used. [5]

Barium chloride can in principle be prepared from barium hydroxide or barium carbonate. These basic salts react with hydrochloric acid to give hydrated barium chloride.


Although inexpensive, barium chloride finds limited applications in the laboratory and industry. In industry, barium chloride is mainly used in the purification of brine solution in caustic chlorine plants and also in the manufacture of heat treatment salts, case hardening of steel.

 [5]  It is also used to make red pigments such as Lithol red and Red Lake C. Its toxicity limits its applicability.


Barium chloride, along with other water-soluble barium salts, is highly toxic. [11] Sodium sulfate and magnesium sulfate are potential antidotes because they form barium sulfate BaSO4, which is relatively non-toxic because of its insolubility.

Related Research Articles

Perchloric acid Chemical compound

Perchloric acid is a mineral acid with the formula HClO4. Usually found as an aqueous solution, this colorless compound is a stronger acid than sulfuric acid, nitric acid and hydrochloric acid. It is a powerful oxidizer when hot, but aqueous solutions up to approximately 70% by weight at room temperature are generally safe, only showing strong acid features and no oxidizing properties. Perchloric acid is useful for preparing perchlorate salts, especially ammonium perchlorate, an important rocket fuel component. Perchloric acid is dangerously corrosive and readily forms potentially explosive mixtures.

Sodium hypochlorite Chemical compound

Sodium hypochlorite is a chemical compound with the formula NaOCl or NaClO, comprising a sodium cation and a hypochlorite anion. It may also be viewed as the sodium salt of hypochlorous acid. The anhydrous compound is unstable and may decompose explosively. It can be crystallized as a pentahydrate NaOCl·5H
, a pale greenish-yellow solid which is not explosive and is stable if kept refrigerated.

The compound hydrogen chloride has the chemical formula HCl and as such is a hydrogen halide. At room temperature, it is a colourless gas, which forms white fumes of hydrochloric acid upon contact with atmospheric water vapor. Hydrogen chloride gas and hydrochloric acid are important in technology and industry. Hydrochloric acid, the aqueous solution of hydrogen chloride, is also commonly given the formula HCl.

Barium hydroxide Chemical compound

Barium hydroxide is a chemical compound with the chemical formula Ba(OH)2. The monohydrate (x = 1), known as baryta or baryta-water, is one of the principal compounds of barium. This white granular monohydrate is the usual commercial form.

Zinc chloride Chemical compound

Zinc chloride is the name of chemical compounds with the formula ZnCl2 and its hydrates. Zinc chlorides, of which nine crystalline forms are known, are colorless or white, and are highly soluble in water. This white salt is hygroscopic and even deliquescent. Samples should therefore be protected from sources of moisture, including the water vapor present in ambient air. Zinc chloride finds wide application in textile processing, metallurgical fluxes, and chemical synthesis. No mineral with this chemical composition is known aside from the very rare mineral simonkolleite, Zn5(OH)8Cl2·H2O.

Barium nitrate Chemical compound

Barium nitrate is the inorganic compound with the chemical formula Ba(NO3)2. It, like most barium salts, is colorless, toxic, and water-soluble. It burns with a green flame and is an oxidizer; the compound is commonly used in pyrotechnics.

Lead(II) chloride Chemical compound

Lead(II) chloride (PbCl2) is an inorganic compound which is a white solid under ambient conditions. It is poorly soluble in water. Lead(II) chloride is one of the most important lead-based reagents. It also occurs naturally in the form of the mineral cotunnite.

Neodymium(III) chloride or neodymium trichloride is a chemical compound of neodymium and chlorine with the formula NdCl3. This anhydrous compound is a mauve-colored solid that rapidly absorbs water on exposure to air to form a purple-colored hexahydrate, NdCl3·6H2O. Neodymium(III) chloride is produced from minerals monazite and bastnäsite using a complex multistage extraction process. The chloride has several important applications as an intermediate chemical for production of neodymium metal and neodymium-based lasers and optical fibers. Other applications include a catalyst in organic synthesis and in decomposition of waste water contamination, corrosion protection of aluminium and its alloys, and fluorescent labeling of organic molecules (DNA).

Manganese(II) chloride Chemical compound

Manganese(II) chloride is the dichloride salt of manganese, MnCl2. This inorganic chemical exists in the anhydrous form, as well as the dihydrate (MnCl2·2H2O) and tetrahydrate (MnCl2·4H2O), with the tetrahydrate being the most common form. Like many Mn(II) species, these salts are pink, with the paleness of the color being characteristic of transition metal complexes with high spin d5 configurations. It is a paramagnetic salt.

Cobalt(II) chloride Chemical compound

Cobalt(II) chloride is an inorganic compound of cobalt and chlorine, with the formula CoCl
. The compound forms several hydrates CoCl
, for n = 1, 2, 6, and 9. Claims of the formation of tri- and tetrahydrates have not been confirmed. The anhydrous form is a blue crystalline solid; the dihydrate is purple and the hexahydrate is pink. Commercial samples are usually the hexahydrate, which is one of the most commonly used cobalt compounds in the lab.

Sodium chlorate Chemical compound

Sodium chlorate is an inorganic compound with the chemical formula NaClO3. It is a white crystalline powder that is readily soluble in water. It is hygroscopic. It decomposes above 300 °C to release oxygen and leaves sodium chloride. Several hundred million tons are produced annually, mainly for applications in bleaching pulp to produce high brightness paper.

Strontium chloride Chemical compound

Strontium chloride (SrCl2) is a salt of strontium and chlorine.

Copper(II) chloride Chemical compound

Copper(II) chloride is the chemical compound with the chemical formula CuCl2. The anhydrous form is yellowish brown but slowly absorbs moisture to form a blue-green dihydrate.

Chromium(III) chloride Chemical compound

Chromium(III) chloride (also called chromic chloride) describes any of several chemical compounds with the formula CrCl3 · xH2O, where x can be 0, 5, and 6. The anhydrous compound with the formula CrCl3 is a violet solid. The most common form of the trichloride is the dark green hexahydrate, CrCl3 · 6 H2O. Chromium chlorides find use as catalysts and as precursors to dyes for wool.

Nickel(II) chloride Chemical compound

Nickel(II) chloride (or just nickel chloride) is the chemical compound NiCl2. The anhydrous salt is yellow, but the more familiar hydrate NiCl2·6H2O is green. Nickel(II) chloride, in various forms, is the most important source of nickel for chemical synthesis. The nickel chlorides are deliquescent, absorbing moisture from the air to form a solution. Nickel salts have been shown to be carcinogenic to the lungs and nasal passages in cases of long-term inhalation exposure.

Iron(II) chloride Chemical compound

Iron(II) chloride, also known as ferrous chloride, is the chemical compound of formula FeCl2. It is a paramagnetic solid with a high melting point. The compound is white, but typical samples are often off-white. FeCl2 crystallizes from water as the greenish tetrahydrate, which is the form that is most commonly encountered in commerce and the laboratory. There is also a dihydrate. The compound is highly soluble in water, giving pale green solutions.

Selenic acid is the inorganic compound with the formula H2SeO4. It is an oxoacid of selenium, and its structure is more accurately described as (HO)2SeO2. It is a colorless compound. Although it has few uses, its derivative sodium selenate is used in the production of glass and animal feeds.

Barium chlorate Chemical compound

Barium chlorate, Ba(ClO3)2, is the barium salt of chloric acid. It is a white crystalline solid, and like all soluble barium compounds, irritant and toxic. It is sometimes used in pyrotechnics to produce a green color. It also finds use in the production of chloric acid.

Barium bromide Chemical compound

Barium bromide is the chemical compound with the formula BaBr2. Like barium chloride, it dissolves well in water and is toxic.

Barium perchlorate is a powerful oxidizing agent, with the formula Ba(ClO4)2. It is used in the pyrotechnic industry.


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