Sodium chromate

Sodium chromate
IUPAC name

Sodium chromate
Other names

Chromic acid, (Na2CrO4), disodium salt
Chromium disodium oxide
Rachromate
Identifiers
CAS number 7775-11-3 Y
PubChem 24488
EC number 231-889-5
UN number 3288
RTECS number GB2955000
Properties
Molecular formula Na2CrO4
Molar mass 161.97 g/mol
Appearance yellow crystals
Density 2.698 g/cm3
Melting point

762 °C
Solubility in water 53 g/100 ml (20 °C)
Structure
Crystal structure orthorhombic (hexagonal above 413 °C)
Thermochemistry
Std enthalpy of
formation ΔfHo298		 −1329 kJ/mol
Hazards
MSDS ICSC 1370
EU Index 024-018-00-3
EU classification Carc. Cat. 2
Muta. Cat. 2
Repr. Cat. 2
Very toxic (T+)
Harmful (Xn)
Corrosive (C)
Dangerous for the environment (N)
R-phrases R45, R46, R60, R61, R21, R25, R26, R34, R42/43, R48/23, R50/53
S-phrases S53, S45, S60, S61
NFPA 704
0
3
0
OX
Flash point Non-flammable
Related compounds
Other anions Sodium dichromate
Sodium molybdate
Sodium tungstate
Other cations Potassium chromate
Calcium chromate
Barium chromate
 Y (verify) (what is: Y/N?)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Sodium chromate (Na2CrO4) is a yellow solid chemical compound used as a corrosion inhibitor in the petroleum industry,[1] a dyeing auxiliary in the textile industry,[1] as a wood preservative,[2] and as a diagnostic pharmaceutical in determining red blood cell volume.[3]

It is obtained from the reaction of sodium dichromate with sodium hydroxide. It is hygroscopic and can form tetra-, hexa-, and decahydrates. Sodium chromate, like other hexavalent chromium compounds, can be carcinogenic.[1]

The substance is a strong oxidant. It is soluble in water,[4] producing a weakly basic solution.[5]

See also

References

  1. ^ a b c Gerd Anger, Jost Halstenberg, Klaus Hochgeschwender, Christoph Scherhag, Ulrich Korallus, Herbert Knopf, Peter Schmidt, Manfred Ohlinger (2005), "Chromium Compounds", Ullmann's Encyclopedia of Industrial Chemistry, Weinheim: Wiley-VCH, doi:10.1002/14356007.a07_067 
  2. ^ "Sodium chromate - Pesticide use statistics for 2005". PAN Pesticides Database. http://www.pesticideinfo.org/Detail_ChemUse.jsp?Rec_Id=PC34364#ChemID. Retrieved 2008-06-20. 
  3. ^ Bracco Diagnostics Inc.. "chromitope sodium (Sodium Chromate, Cr 51) injection, solution". DailyMed. http://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?id=6525. Retrieved 2008-06-20. 
  4. ^ "Sodium chromate". inchem. http://www.inchem.org/documents/icsc/icsc/eics1370.htm. Retrieved 2008-06-20. 
  5. ^ Record of Sodium chromate in the GESTIS Substance Database from the IFA