Beryllium hydroxide
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| Names | |
|---|---|
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IUPAC name
Beryllium hydroxide
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| Other names
Hydrated beryllia
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| Identifiers | |
13327-32-7 
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| 3D model (Jmol) | Interactive image |
| ChEBI |
CHEBI:35102 
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| ChemSpider |
24727701
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| ECHA InfoCard | 100.033.048 |
| EC Number | 236-368-6 |
| 1024 | |
| MeSH | Beryllium+hydroxide |
| PubChem | 25879 |
| RTECS number | DS3150000 |
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| Properties | |
| BeH2O2 | |
| Molar mass | 43.03 g·mol−1 |
| Appearance | Vivid white, opaque crystals |
| Density | 1.92 g cm−3 |
| Melting point | 1,000 °C (1,830 °F; 1,270 K) (decomposes) |
| slightly soluble | |
| Structure | |
| Linear | |
| Thermochemistry | |
| 1.443 J K−1 | |
|
Std molar
entropy (S |
47 J·mol−1·K−1 |
|
Std enthalpy of
formation (ΔfH |
-904 kJ mol−1 |
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Gibbs free energy (ΔfG˚)
|
-818 kJ/mol |
| Hazards | |
| Main hazards | Carcinogenic |
| Lethal dose or concentration (LD, LC): | |
|
LD50 (median dose)
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4 mg kg−1 (intravenous, rat) |
| US health exposure limits (NIOSH): | |
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PEL (Permissible)
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TWA 0.002 mg/m3 C 0.005 mg/m3 (30 minutes), with a maximum peak of 0.025 mg/m3 (as Be) |
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REL (Recommended)
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Ca C 0.0005 mg/m3 (as Be) |
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IDLH (Immediate danger)
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Ca [4 mg/m3 (as Be)] |
| Related compounds | |
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Related compounds
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Aluminium oxide |
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Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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 (what is ?) |
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| Infobox references | |
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. The natural pure beryllium hydroxide is rare (in form of the mineral behoite, orthorhombic) or very rare (clinobehoite, monoclinic). 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. This has the same structure as zinc hydroxide, Zn(OH)2, with tetrahedral beryllium centers.
With alkalis it dissolves to form the tetrahydroxidoberyllate(2-) anion. With sodium hydroxide solution:
With acids, beryllium salts are formed. For example, with sulfuric acid, H2SO4, beryllium sulfate is formed:
Beryllium hydroxide dehydrates at 400 °C to form the soluble white powder, beryllium oxide:
Further heating at higher temperature produces acid insoluble BeO.
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