Aluminium hydroxide

This article is about Al(OH)3. For AlOH, see aluminium monohydroxide.

Aluminium hydroxide
Unit cell ball and stick model of aluminium hydroxide
Sample of aluminium hydroxide in a vial
Names
Preferred IUPAC name
Aluminium hydroxide
Systematic IUPAC name
Trihydroxidoaluminium
Other names
  • Aluminic acid
  • Aluminic hydroxide
  • Alumanetriol
  • Aluminium(III) hydroxide
  • Aluminium hydroxide
  • Aluminium trihydroxide
  • Hydrated alumina
  • Orthoaluminic acid
Identifiers
3D model (JSmol)
ChEBI
ChEMBL
ChemSpider
DrugBank
ECHA InfoCard 100.040.433 Edit this at Wikidata
KEGG
RTECS number
  • BD0940000
UNII
  • InChI=1S/Al.3H2O/h;3*1H2/q+3;;;/p-3 checkY
    Key: WNROFYMDJYEPJX-UHFFFAOYSA-K
    A02AB02 (WHO) (algeldrate) ☒N
  • InChI=1/Al.3H2O/h;3*1H2/q+3;;;/p-3
    Key: WNROFYMDJYEPJX-DFZHHIFOAJ
  • [OH-].[OH-].[OH-].[Al+3]
Properties[1][2]
Al(OH)3
Molar mass 78.003 g·mol−1
Appearance White amorphous powder
Density 2.42 g/cm3, solid
Melting point 300 °C (572 °F; 573 K)
0.0001 g/(100 mL)
3×10−34
Solubility soluble in acids and alkalis
Acidity (pKa) >7
Isoelectric point 7.7
Thermochemistry[3]
−1277 kJ·mol−1
Pharmacology[4]
A02AB01 (WHO)
Hazards
GHS labelling:
no GHS pictograms
no hazard statements
P261, P264, P271, P280, P304+P340, P305+P351+P338, P312, P337+P313
NFPA 704 (fire diamond)
NFPA 704 four-colored diamondHealth 1: Exposure would cause irritation but only minor residual injury. E.g. turpentineFlammability 0: Will not burn. E.g. waterInstability 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogenSpecial hazards (white): no code
1
0
0
Flash point Non-flammable
Lethal dose or concentration (LD, LC):
>5000 mg/kg (rat, oral)
Safety data sheet (SDS) External MSDS
Related compounds
Other anions
 None
Related compounds
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 ?)

Aluminium hydroxide, Al(OH)3, is found in nature as the mineral gibbsite (also known as hydrargillite) and its three much rarer polymorphs: bayerite, doyleite, and nordstrandite. Aluminium hydroxide is amphoteric, i.e., it has both basic and acidic properties. Closely related are aluminium oxide hydroxide, AlO(OH), and aluminium oxide or alumina (Al2O3), the latter of which is also amphoteric. These compounds together are the major components of the aluminium ore bauxite. Aluminium hydroxide also forms a gelatinous precipitate in water.

  1. ^ For solubility product: "Solubility product constants". Archived from the original on 15 June 2012. Retrieved 17 May 2012.
  2. ^ For isoelectric point: Gayer, K. H.; Thompson, L. C.; Zajicek, O. T. (September 1958). "The solubility of aluminum hydroxide in acidic and basic media at 25 ?c". Canadian Journal of Chemistry. 36 (9): 1268–1271. doi:10.1139/v58-184. ISSN 0008-4042.
  3. ^ Zumdahl, Steven S. (2009). Chemical Principles (6th ed.). Houghton Mifflin Company. ISBN 978-0-618-94690-7.
  4. ^ Black, Ronald A.; Hill, D. Ashley (15 June 2003). "Over-the-Counter Medications in Pregnancy". American Family Physician. 67 (12): 2517–2524. ISSN 0002-838X. PMID 12825840. Retrieved 1 July 2017.