Barium carbonate

Barium carbonate is the inorganic compound with the formula BaCO3. Like most alkaline earth metal carbonates, it is a white salt that is poorly soluble in water. It occurs as the mineral known as witherite. In a commercial sense, it is one of the most important barium compounds.[5]

Barium carbonate
Skeletal formula of barium carbonate
Powder of barium carbonate
Barium-carbonate-from-xtal-3D-SF.png
Names
Other names
Identifiers
  • 513-77-9 checkY
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.007.426 Edit this at Wikidata
EC Number
  • 208-167-3
RTECS number
  • CQ8600000
UNII
UN number 1564
  • InChI=1S/CH2O3.Ba/c2-1(3)4;/h(H2,2,3,4);/q;+2/p-2 checkY
    Key: AYJRCSIUFZENHW-UHFFFAOYSA-L checkY
  • InChI=1/CH2O3.Ba/c2-1(3)4;/h(H2,2,3,4);/q;+2/p-2
    Key: AYJRCSIUFZENHW-NUQVWONBAT
  • [Ba+2].[O-]C([O-])=O
  • C(=O)([O-])[O-].[Ba+2]
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]
2.58·10−9
Solubility decomposes in acid
insoluble in methanol
-58.9·10−6 cm3/mol
1.676
Thermochemistry
85.35 J/mol·K[1]
112 J/mol·K[2]
-1219 kJ/mol[2]
-1139 kJ/mol[1]
Hazards
Safety data sheet ICSC 0777
GHS pictograms GHS07: Exclamation mark[3]
GHS Signal word Warning
H302[3]
NFPA 704 (fire diamond)
Flash point Non-flammable
Lethal dose or concentration (LD, LC):
418 mg/kg, oral (rat)
Related compounds
Other cations
Beryllium carbonate
Magnesium carbonate
Calcium carbonate
Strontium carbonate
Radium carbonate
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
☒N verify (what is checkY☒N ?)
Infobox references

PreparationEdit

Barium carbonate is made commercially from barium sulfide with by treatment with sodium carbonate at 60 to 70 °C (soda ash method) or, more commonly carbon dioxide at 40 to 90 °C:

In the soda ash process, an aqueous solution of barium sulfide is treated with sodium carbonate:[5]

BaS + H2O + CO2 → BaCO3 + H2S

ReactionsEdit

Barium carbonate reacts with acids such as hydrochloric acid to form soluble barium salts, such as barium chloride:

BaCO
3
+ 2 HCl → BaCl
2
+ CO
2
+ H
2
O

Pyrolysis of barium carbonate gives barium oxide.[6]

UsesEdit

It is mainly used to remove sulfate impurities from feedstock of the chlor-alkali process. Otherwise it is a common precursor to barium-containing compounds such as ferrites.[5]

Other usesEdit

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 some claim that it can leach from glazes into food and drink. To provide a safe means of use, BaO is often used in fritted form.

In the brick, tile, earthenware and pottery industries barium carbonate is added to clays to precipitate soluble salts (calcium sulfate and magnesium sulfate) that cause efflorescence.

ReferencesEdit

  1. ^ a b c d "Barium carbonate".
  2. ^ a b Zumdahl, Steven S. (2009). Chemical Principles 6th Ed. Houghton Mifflin Company. ISBN 978-0-618-94690-7.
  3. ^ a b Sigma-Aldrich Co., Barium carbonate. Retrieved on 2014-05-06.
  4. ^ Sciences labs MSDS
  5. ^ a b c Kresse, Robert; Baudis, Ulrich; Jäger, Paul; Riechers, H. Hermann; Wagner, Heinz; Winkler, Jochen; Wolf, Hans Uwe (2007). "Barium and Barium Compounds". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a03_325.pub2.
  6. ^ P. Ehrlich (1963). "Barium Oxide". In G. Brauer (ed.). Handbook of Preparative Inorganic Chemistry, 2nd Ed. 1. NY,NY: Academic Press. pp. 933–944.

[1]

External linksEdit