Beryllium hydroxide

Last updated
Beryllium hydroxide
Be(OH)2.png
Names
IUPAC name
Beryllium hydroxide
Other names
  • Beryllic acid
  • Hydrated beryllia
Identifiers
3D model (JSmol)
ChEBI
ChemSpider
ECHA InfoCard 100.033.048 OOjs UI icon edit-ltr-progressive.svg
EC Number
  • 236-368-6
1024
MeSH Beryllium+hydroxide
PubChem CID
RTECS number
  • DS3150000
UNII
  • InChI=1S/Be.2H2O/h;2*1H2/q+2;;/p-2 Yes check.svgY
    Key: WPJWIROQQFWMMK-UHFFFAOYSA-L Yes check.svgY
  • InChI=1/Be.2H2O/h;2*1H2/q+2;;/p-2
    Key: WPJWIROQQFWMMK-NUQVWONBAB
  • O[Be]O
Properties
BeH2O2
Molar mass 43.026 g·mol−1
AppearanceVivid white, opaque crystals
Density 1.92 g cm−3 [1]
Melting point (decomposes)
0.0000023965 g/L
6.92×10−22 [2]
Acidity (pKa)3.7 [3]
Structure
Linear
Thermochemistry
1.443 J K−1
Std molar
entropy (S⦵298)
47 J·mol−1·K−1 [4]
−904 kJ mol−1 [4]
−818 kJ/mol
Hazards
Occupational safety and health (OHS/OSH):
Main hazards
Carcinogenic
GHS labelling:
GHS-pictogram-skull.svg GHS-pictogram-silhouette.svg GHS-pictogram-pollu.svg [5]
Danger
NFPA 704 (fire diamond)
NFPA 704.svgHealth 4: Very short exposure could cause death or major residual injury. E.g. VX gasFlammability 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
4
0
0
Lethal dose or concentration (LD, LC):
4 mg kg−1 (intravenous, rat)
NIOSH (US health exposure limits):
PEL (Permissible)
TWA 0.002 mg/m3
C 0.005 mg/m3 (30 minutes), with a maximum peak of 0.025 mg/m3 (as Be) [6]
REL (Recommended)
Ca C 0.0005 mg/m3 (as Be) [6]
IDLH (Immediate danger)
Ca [4 mg/m3 (as Be)] [6]
Related compounds
Related compounds
 Aluminium oxide

Magnesium hydroxide

Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
X mark.svgN  verify  (what is  Yes check.svgYX mark.svgN ?)

Beryllium hydroxide, Be(OH)2, is an amphoteric hydroxide, dissolving in both acids and alkalis. Industrially, it is produced as a by-product in the extraction of beryllium metal from the ores beryl and bertrandite. [7] The natural pure beryllium hydroxide is rare (in form of the mineral behoite, orthorhombic) or very rare (clinobehoite, monoclinic). [8] [9] When alkali is added to beryllium salt solutions the α-form (a gel) is formed. If this left to stand or boiled, the rhombic β-form precipitates. [10] This has the same structure as zinc hydroxide, Zn(OH)2, with tetrahedral beryllium centers. [11]

Reactions

Beryllium hydroxide is difficult to dissolve in water. With alkalis it dissolves to form the tetrahydroxoberyllate (also known as tetrahydroxidoberyllate) anion, [Be(OH)4]2−. [12] With sodium hydroxide solution:

2 NaOH(aq) + Be(OH)2(s) → Na2[Be(OH)4](aq)

With acids, beryllium salts are formed. [12] For example, with sulfuric acid, H2SO4, beryllium sulfate is formed:

Be(OH)2 + H2SO4 → BeSO4 + 2 H2O

Beryllium hydroxide dehydrates at 400 °C to form the soluble white powder, beryllium oxide: [12]

Be(OH)2 → BeO + H2O

Further heating at higher temperature produces acid insoluble BeO. [12]

References

  1. ↑ Pradyot Patnaik. Handbook of Inorganic Chemicals. McGraw-Hill, 2002, ISBN   0-07-049439-8
  2. ↑ John Rumble (June 18, 2018). CRC Handbook of Chemistry and Physics (99 ed.). CRC Press. pp. 4–47. ISBN   978-1138561632.
  3. ↑ Handbook of Chemistry and Physics. Cleveland, Ohio: Chemical Rubber Publishing Company. 1951. pp. 1636–1637.
  4. 1 2 Zumdahl, Steven S. (2009). Chemical Principles 6th Ed. Houghton Mifflin Company. ISBN   978-0-618-94690-7.
  5. ↑ "Beryllium Hydroxide". American Elements. Retrieved 5 July 2023.
  6. 1 2 3 NIOSH Pocket Guide to Chemical Hazards. "#0054". National Institute for Occupational Safety and Health (NIOSH).
  7. ↑ Jessica Elzea Kogel, Nikhil C. Trivedi, James M. Barker and Stanley T. Krukowski, 2006, Industrial Minerals & Rocks: Commodities, Markets, and Uses, 7th edition, SME, ISBN   0-87335-233-5
  8. ↑ Mindat, http://www.mindat.org/min-603.html
  9. ↑ Mindat, http://www.mindat.org/min-1066.html
  10. ↑ Mary Eagleson, 1994, Concise encyclopedia chemistry, Walter de Gruyter, ISBN   3-11-011451-8
  11. ↑ Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. ISBN   978-0-08-037941-8.
  12. 1 2 3 4 Egon Wiberg, Arnold Frederick Holleman (2001) Inorganic Chemistry, Elsevier ISBN   0-12-352651-5