Barium chloride is an inorganic compound with the formula BaCl2. 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.
Muryate of Barytes
Barium dichloride crystals
Neutral barium chloride
3D model (JSmol)
CompTox Dashboard (EPA)
|Molar mass||208.23 g/mol (anhydrous) |
244.26 g/mol (dihydrate)
|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|
|orthogonal (anhydrous) |
|123.9 J/(k mol)|
Std enthalpy of
|Occupational safety and health (OHS/OSH):|
|Highly toxic, corrosive|
|H301, H302, H332|
|P261, P264, P270, P271, P301+P310, P304+P312, P304+P340, P312, P321, P330, P405, P501|
|NFPA 704 (fire diamond)|
|Lethal dose or concentration (LD, LC):|
LD50 (median dose)
|78 mg/kg (rat, oral)|
50 mg/kg (guinea pig, oral)
LDLo (lowest published)
|112 mg Ba/kg (rabbit, oral)|
59 mg Ba/kg (dog, oral)
46 mg Ba/kg (mouse, oral)
|NIOSH (US health exposure limits):|
|TWA 0.5 mg/m3|
|TWA 0.5 mg/m3|
IDLH (Immediate danger)
|Safety data sheet (SDS)||NIH BaCl|
|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).
(what is ?)
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. The coordination of Ba2+ is 8 in the fluorite structure and 9 in the cotunnite structure. 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.
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.
Oxalate effects a similar reaction:
When it is mixed with sodium hydroxide, it gives the dihydroxide, which is moderately soluble in water.
This first step requires high temperatures.
In place of HCl, chlorine can be used.
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.
 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. Sodium sulfate and magnesium sulfate are potential antidotes because they form barium sulfate BaSO4, which is relatively non-toxic because of its insolubility.