Names | |
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Systematic IUPAC name
Beryllium iodide | |
Identifiers | |
3D model (
JSmol)
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ChemSpider | |
ECHA InfoCard | 100.029.199 |
PubChem
CID
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UNII | |
CompTox Dashboard (
EPA)
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Properties | |
Be I2 | |
Molar mass | 262.821 g/mol |
Appearance | colorless needle-like crystals |
Density | 4.325 g/cm3 |
Melting point | 480 °C (896 °F; 753 K) |
Boiling point | 590 °C (1,094 °F; 863 K) [1] |
reacts with water [1][ citation needed] | |
Solubility | Slightly soluble in
CS2 Soluble in ethanol, diethyl ether [2] |
Structure | |
orthorhombic | |
Thermochemistry | |
Heat capacity (C)
|
71.14 J/(mol × K) |
Std molar
entropy (S⦵298) |
130 J/mol K |
Std enthalpy of
formation (ΔfH⦵298) |
-192.62 kJ/mol |
Gibbs free energy (ΔfG⦵)
|
-210 kJ/mol |
Std enthalpy of
combustion (ΔcH⦵298) |
19 kJ/mol |
Hazards | |
Occupational safety and health (OHS/OSH): | |
Main hazards
|
see Berylliosis |
NFPA 704 (fire diamond) | |
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) [3] |
REL (Recommended)
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Ca C 0.0005 mg/m3 (as Be) [3] |
IDLH (Immediate danger)
|
Ca [4 mg/m3 (as Be)] [3] |
Related compounds | |
Other
anions
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Beryllium fluoride Beryllium chloride Beryllium bromide |
Other
cations
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magnesium iodide calcium iodide strontium iodide barium iodide |
Except where otherwise noted, data are given for materials in their
standard state (at 25 °C [77 °F], 100 kPa).
|
Beryllium iodide is the inorganic compound with the formula BeI2. It is a hygroscopic white solid.
Beryllium iodide can be prepared by reacting beryllium metal with elemental iodine at temperatures of 500 °C to 700 °C: [1]
Beryllium iodide is also formed when beryllium carbide reacts with hydrogen iodide in the gas phase:
Beryllium iodide reacts with fluorine giving beryllium fluoride and fluorides of iodine, with chlorine giving beryllium chloride, and with bromine giving beryllium bromide.
Two forms ( polymorphs) of BeI2 are known. Both structures consist tetrahedral Be2+ centers interconnected by doubly bridging iodide ligands. One form consist of edge-sharing polytetrahedra. The other form resembles zinc iodide with interconnected adamantane-like cages. [4]
Beryllium iodide can be used in the preparation of high-purity beryllium by the decomposition of the compound on a hot tungsten filament.