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Names | |
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Other names | |
Identifiers | |
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3D model (JSmol) | |
ChEBI | |
ChemSpider |
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ECHA InfoCard | 100.007.426![]() |
EC Number |
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RTECS number |
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UNII | |
UN number | 1564 |
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Properties | |
BaCO3 | |
Molar mass | 197.34 g/mol |
Appearance | white crystals |
Odor | odorless |
Density | 4.286 g/cm3 |
Melting point | 811 °C (1,492 °F; 1,084 K) polymorphic transformation |
Boiling point | 1,450 °C (2,640 °F; 1,720 K) decomposes[1] from 1360 °C |
16 mg/L (8.8°C) 22 mg/L (18 °C) 24 mg/L (20 °C) 24 mg/L (24.2 °C)[1] | |
Solubility product (Ksp) | 2.58·10−9 |
Solubility | decomposes inacid insoluble inmethanol |
−58.9·10−6 cm3/mol | |
Refractive index (nD) | 1.676 |
Structure | |
orthorhombic | |
Thermochemistry | |
85.35 J/mol·K[1] | |
Std molar entropy(S⦵298) | 112 J/mol·K[2] |
Std enthalpy of formation(ΔfH⦵298) | −1219 kJ/mol[2] |
Gibbs free energy(ΔfG⦵) | −1139 kJ/mol[1] |
Hazards | |
GHS labelling: | |
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Warning | |
H302[3] | |
NFPA 704 (fire diamond) | |
Flash point | Non-flammable |
Lethal dose or concentration (LD, LC): | |
LD50 (median dose) | 418 mg/kg, oral (rat) |
Safety data sheet (SDS) | ICSC 0777 |
Related compounds | |
Othercations | Beryllium carbonate Magnesium carbonate Calcium carbonate Strontium carbonate Radium carbonate |
Except where otherwise noted, data are given for materials in theirstandard state (at 25 °C [77 °F], 100 kPa). |
Barium carbonate is theinorganic compound with the formula BaCO3. Like mostalkaline earth metalcarbonates, it is a white salt that is poorly soluble in water. It occurs as the mineral known aswitherite. In a commercial sense, it is one of the most importantbarium compounds.[5]
Barium carbonate is made commercially frombarium sulfide by treatment withsodium carbonate at 60 to 70 °C (soda ash method) or, more commonlycarbon dioxide at 40 to 90 °C:
In the soda ash process, an aqueous solution of barium sulfide is treated with sodium carbonate:[5]
Barium carbonate reacts with acids such ashydrochloric acid to form soluble barium salts, such asbarium chloride:
Pyrolysis of barium carbonate givesbarium oxide.[6]
It is mainly used to remove sulfate impurities from feedstock of thechlor-alkali process. Otherwise it is a common precursor to barium-containing compounds such as ferrites.[5]
Barium carbonate is widely used in the ceramics industry as an ingredient in glazes. It acts as a flux, a matting and crystallizing agent and combines with certain colouring oxides to produce unique colours not easily attainable by other means. Its use is somewhat controversial since it can leach from glazes into food and drink. To reduce toxicity concerns, it is often substituted withstrontium carbonate, which behaves in a similar way in glazes but is of lower toxicity.
In the brick, tile, earthenware and pottery industries barium carbonate is added to clays to precipitate soluble salts (calcium sulfate andmagnesium sulfate) that causeefflorescence.
It is sometimes used as an "energiser" in theCase-hardening process.
"Preparation and Characterization of Barium Carbonate Nanoparticles - Volume 2 Number 4 (Aug. 2011) - IJCEA".www.ijcea.org. Retrieved2017-12-13.