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Names | |||
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IUPAC name
Magnesium iodide
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Identifiers | |||
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3D model (
JSmol)
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ChemSpider | |||
ECHA InfoCard | 100.030.738 | ||
EC Number |
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PubChem
CID
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UNII |
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CompTox Dashboard (
EPA)
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Properties | |||
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Molar mass |
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Appearance | white crystalline solid | ||
Odor | odorless | ||
Density |
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Melting point | 637 °C (1,179 °F; 910 K) (anhydrous, decomposes) 41 °C (octahydrate, decomposes) | ||
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Solubility | soluble in ether, alcohol and ammonia | ||
−111.0·10−6 cm3/mol | |||
Structure | |||
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Thermochemistry | |||
Heat capacity (C)
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74 J/(mol·K) | ||
Std molar
entropy (S⦵298) |
134 J/(mol·K) | ||
Std enthalpy of
formation (ΔfH⦵298) |
−364 kJ/mol | ||
Hazards | |||
GHS labelling: | |||
Warning | |||
H315, H319 | |||
NFPA 704 (fire diamond) | |||
Related compounds | |||
Other
anions
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Other
cations
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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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Magnesium iodide is an inorganic compound with the chemical formula Mg I2. It forms various hydrates MgI2·xH2O. Magnesium iodide is a salt of magnesium and hydrogen iodide. These salts are typical ionic halides, being highly soluble in water.
Magnesium iodide has few commercial uses, but can be used to prepare compounds for organic synthesis.
Magnesium iodide can be prepared from magnesium oxide, magnesium hydroxide, and magnesium carbonate by treatment with hydroiodic acid: [3]
Magnesium iodide is stable at high heat under a hydrogen atmosphere, but decomposes in air at normal temperatures, turning brown from the release of elemental iodine. When heated in air, it decomposes completely to magnesium oxide. [4]
Another method to prepare MgI2 is mixing powdered elemental iodine and magnesium metal. In order to obtain anhydrous MgI2, the reaction should be conducted in a strictly anhydrous atmosphere; dry-diethyl ether can be used as a solvent.
Usage of magnesium iodide in the Baylis-Hillman reaction tends to give ( Z)- vinyl compounds. [5]
Demethylation of certain aromatic methyl ethers can be afforded using magnesium iodide in diethyl ether. [6]