Sodium aluminium sulfate

From WikiChem
(Redirected from Sodium aluminium sulphate)
Jump to: navigation, search
Sodium aluminium sulfate dodecahydrate
IUPAC name Aluminium sodium bis(sulfate) — water (1:12)
Other names Sodium alum
Soda alum
E521
Identifiers
InChI InChI=1/Al.Na.2H2O4S.12H2O/c;;2*1-5(2,3)4;;;;;;;;;;;;/h;;2*(H2,1,​2,3,4);12*1H2/q+3;+1;;;;;;;;;;;;;;/p-4
InChIKey ZEMWIYASLJTEHQ-XBHQNQODAL
Standard InChI InChI=1S/Al.Na.2H2O4S.12H2O/c;;2*1-5(2,3)4;;;;;;;;;;;;/h;;2*(H2,1​,2,3,4);12*1H2/q+3;+1;;;;;;;;;;;;;;/p-4
Standard InChIKey ZEMWIYASLJTEHQ-UHFFFAOYSA-J
CAS number [7784-28-3]
EC number 233-277-3
ChemSpider 22972
Properties[1]
Chemical formula NaAl(SO4)2·12H2O
Molar mass 458.28 g/mol
Appearance while crystalline powder
Density 1.6754 (20 °C)
Melting point

61 °C

Solubility in water 208 g/100 ml (15 °C)
Refractive index (nD) 1.4388
Structure[2]
Crystal structure Cubic, cP96
Space group Pa3, No. 205
Lattice constant a = 1221.4 pm
Coordination geometry Octahedral (Na+)
Octahedral (Al3+)
Hazards
EU index number not listed
Flash point non-flammable
Related compounds
Other cations Ammonium aluminium sulfate
Potassium aluminium sulfate
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Sodium aluminium sulfate (anhydrous)
IUPAC name Aluminium sodium bis(sulfate)
Identifiers
InChI InChI=1/Al.Na.2H2O4S/c;;2*1-5(2,3)4/h;;2*(H2,1,2,3,4)/q+3;+1;;/p-​4
InChIKey GJPYYNMJTJNYTO-XBHQNQODAI
Standard InChI InChI=1S/Al.Na.2H2O4S/c;;2*1-5(2,3)4/h;;2*(H2,1,2,3,4)/q+3;+1;;/p​-4
Standard InChIKey GJPYYNMJTJNYTO-UHFFFAOYSA-J
CAS number [10102-71-3]
EC number 233-277-3
ChemSpider 23313
Properties[1]
Chemical formula NaAl(SO4)2
Molar mass 242.10 g/mol
Appearance while crystalline powder
Solubility in water 110 g/100 ml (15 °C)
Hazards
EU index number not listed
Flash point non-flammable
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)

Sodium aluminium sulfate, NaAl(SO4)2·12H2O or Na2SO4·Al2(SO4)3·24H2O, also known as soda alum or sodium alum, is a form of alum used in the acidity regulator of food (E521) as well as in the manufacture of baking powder. It is also a common mordant for the preparation of hematoxylin solutions for staining cell nuclei in histopathology.

The classical cubic alum structure is the dodecahydrate, which is known in mineralogy as alum-(Na).[3][4] Two other rare mineral forms are known: mendozite (undecahydrate)[5] and tamarugite (hexahydrate).[6]

References

  1. 1.0 1.1 CRC Handbook of Chemistry and Physics, 62nd ed.; Weast, Robert C., Ed.; CRC Press: Boca Raton, FL, 1981; p B-146. ISBN 0-8493-0462-8.
  2. Cromer, D. T.; Kay, M. I.; Larson, A. C. Refinement of the alum structures. II. X-ray and neutron diffraction of NaAl(SO4)2·12H2O, γ-alum. Acta Crystallogr. 1967, 22 (2), 182–87. DOI: 10.1107/S0365110X67000313.
  3. Burke, Ernst A.J. Tidying up mineral names: an IMA-CNMNC scheme for suffixes, hyphens and diacritical marks. Mineralogical Record 2008, 39 (2), 131–35, <http://pubsites.uws.edu.au/ima-cnmnc/tidyingupnames.pdf>.
  4. Alum-(Na), <http://webmineral.com/data/Alum-%28Na%29.shtml> (accessed 28 November 2009), WebMineral.com. Alum-(Na), <http://www.mindat.org/show.php?id=3703> (accessed 28 November 2009), MinDat.org.
  5. Mendozite, <http://webmineral.com/data/Mendozite.shtml> (accessed 28 November 2009), WebMineral.com. Mendozite, <http://www.mindat.org/show.php?id=2643> (accessed 28 November 2009), MinDat.org.
  6. Tamarugite, <http://www.webmineral.com/data/Tamarugite.shtml> (accessed 28 November 2009), WebMineral.com. Tamarugite, <http://www.mindat.org/show.php?id=3878> (accessed 28 November 2009), MinDat.org.

External links

Error creating thumbnail: Unable to save thumbnail to destination
Wikipedia-logo.png This page was originally imported from Wikipedia, specifically this version of the article "Sodium aluminium sulfate". Please see the history page on Wikipedia for the original authors. This WikiChem article may have been modified since it was imported. It is licensed under the Creative Commons Attribution–Share Alike 3.0 Unported license.