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| Names | |
|---|---|
| IUPAC name Beryllium chloride | |
| Identifiers | |
3D model (JSmol) |
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| ChemSpider |
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| ECHA InfoCard | 100.029.197 |
| RTECS number |
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| UNII | |
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| Properties | |
| BeCl2 | |
| Molar mass | 79.9182 g/mol |
| Appearance | White or yellow crystals |
| Density | 1.899 g/cm3, solid |
| Melting point | 399 °C (750 °F; 672 K) |
| Boiling point | 482 °C (900 °F; 755 K) |
| 15.1 g/100 mL (20 °C) | |
| Solubility | soluble inalcohol,ether,benzene, andpyridine slightly soluble inchloroform andsulfur dioxide |
| Structure | |
| hexagonal | |
| polymer | |
| Thermochemistry | |
| 7.808 J/K or 71.1 J/mol K | |
Std molar entropy(S⦵298) | 63 J/mol K |
Std enthalpy of formation(ΔfH⦵298) | −6.136 kJ/g or −494 kJ/mol |
Gibbs free energy(ΔfG⦵) | −468 kJ/mol |
Std enthalpy of combustion(ΔcH⦵298) | 16 kJ/mol |
| Hazards | |
| Lethal dose or concentration (LD, LC): | |
LD50 (median dose) | 86 mg/kg (rat, oral) |
| 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)[1] |
REL (Recommended) | Ca C 0.0005 mg/m3 (as Be)[1] |
IDLH (Immediate danger) | Ca [4 mg/m3 (as Be)][1] |
| Related compounds | |
Otheranions | Beryllium fluoride Beryllium bromide Beryllium iodide |
Othercations | Magnesium chloride Calcium chloride Strontium chloride Barium chloride Radium chloride |
Except where otherwise noted, data are given for materials in theirstandard state (at 25 °C [77 °F], 100 kPa). | |
Beryllium chloride is aninorganic compound with theformula BeCl2. It is a colourless,hygroscopic solid that dissolves well in many polar solvents. Its properties are similar to those ofaluminium chloride, due toberyllium'sdiagonal relationship withaluminium.
Beryllium chloride is prepared by reaction of the metal with chlorine at high temperatures:[2]
BeCl2 can also be prepared bycarbothermal reduction ofberyllium oxide in the presence of chlorine.[3] BeCl2 can be prepared by treatingberyllium withhydrogen chloride.
Two forms (polymorphs) of BeCl2 are known. Both structures consist tetrahedral Be2+ centers interconnected by doubly bridging chloride ligands. One form consist of edge-sharing polytetrahedra. The other form resembleszinc iodide with interconnectedadamantane-like cages.[4] In contrast,BeF2 is a3-dimensional polymer, with a structure akin to that ofquartz.
In the gas phase, BeCl2 exists both as alinear monomer and abridgeddimer with two bridging chlorine atoms where the beryllium atom is3-coordinate.[5] The linear shape of the monomeric form is as predicted byVSEPR theory. The linear shape contrasts with the monomeric forms of some of thedihalides of the heavier members of group 2, e.g.CaF2,SrF2,BaF2,SrCl2,BaCl2,BaBr2, andBaI2, which are all non-linear.[5] Beryllium chloride dissolves to give tetrahedral [Be(OH2)4]2+ ion in aqueous solutions as confirmed byvibrational spectroscopy.[6]
When treated with water, beryllium chloride forms atetrahydrate, BeCl2•4H2O ([Be(H2O)4]Cl2). BeCl2 is also soluble in some ethers.[7][8]
When suspended in diethyl ether, beryllium chloride converts to the colorless dietherate:[9]
This ether ligand can be displaced by otherLewis bases.
Beryllium chloride forms complexes with phosphines.[10]
Beryllium chloride is used as a raw material for theelectrolysis of beryllium, and as acatalyst forFriedel-Crafts reactions.
