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 chromate (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

• Chromate

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