Beryllium hydroxide

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.[5] The natural pure beryllium hydroxide is rare (in form of the mineral behoite, orthorhombic) or very rare (clinobehoite, monoclinic).[6][7] 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.[8] This has the same structure as zinc hydroxide, Zn(OH)2, with tetrahedral beryllium centers.[9]

Beryllium hydroxide
Names
IUPAC name
Beryllium hydroxide
Other names
Hydrated beryllia
Identifiers
3D model (JSmol)
ChEBI
ChemSpider
ECHA InfoCard 100.033.048
EC Number
  • 236-368-6
1024
MeSH Beryllium+hydroxide
RTECS number
  • DS3150000
UNII
  • InChI=1S/Be.2H2O/h;2*1H2/q+2;;/p-2 Y
    Key: WPJWIROQQFWMMK-UHFFFAOYSA-L Y
  • 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
Appearance Vivid white, opaque crystals
Density 1.92 g cm−3[1]
Melting point (decomposes)
0.0000023965 g/L
6.92×10−22[2]
Structure
Linear
Thermochemistry
1.443 J K−1
47 J·mol−1·K−1[3]
-904 kJ mol−1[3]
-818 kJ/mol
Hazards
Occupational safety and health (OHS/OSH):
Main hazards
 Carcinogenic
GHS labelling:
Danger
NFPA 704 (fire diamond)
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)[4]
REL (Recommended)
 Ca C 0.0005 mg/m3 (as Be)[4]
IDLH (Immediate danger)
 Ca [4 mg/m3 (as Be)][4]
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).
N verify (what is YN ?)
Infobox references

Reactions

Beryllium hydroxide is difficult to dissolve in water. With alkalis it dissolves to form the tetrahydroxoberyllate/tetrahydroxidoberyllate anion, [Be(OH)4]2−.[10] With sodium hydroxide solution:

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

With acids, beryllium salts are formed.[10] For example, with sulfuric acid, H2SO4, beryllium sulfate is formed:

Be(OH)2 + H2SO4 → BeSO4 + 2H2O

Beryllium hydroxide dehydrates at 400 °C to form the soluble white powder, beryllium oxide:[10]

Be(OH)2 → BeO + H2O

Further heating at higher temperature produces acid insoluble BeO.[10]

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 1138561630.
  3. Zumdahl, Steven S. (2009). Chemical Principles 6th Ed. Houghton Mifflin Company. ISBN 978-0-618-94690-7.
  4. NIOSH Pocket Guide to Chemical Hazards. "#0054". National Institute for Occupational Safety and Health (NIOSH).
  5. 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
  6. Mindat, http://www.mindat.org/min-603.html
  7. Mindat, http://www.mindat.org/min-1066.html
  8. Mary Eagleson, 1994, Concise encyclopedia chemistry, Walter de Gruyter, ISBN 3-11-011451-8
  9. Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. ISBN 978-0-08-037941-8.
  10. Egon Wiberg, Arnold Frederick Holleman (2001) Inorganic Chemistry, Elsevier ISBN 0-12-352651-5
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