Zinc bromide
 |
|
 |
|
| Names | |
|---|---|
|
IUPAC name
Zinc bromide
|
|
| Other names
Zinc(II) bromide,
Zinc dibromide |
|
| Identifiers | |
|
3D model (Jmol)
|
|
| ChemSpider | |
| ECHA InfoCard | 100.028.836 |
|
PubChem CID
|
|
| RTECS number | ZH1150000 |
| UNII | |
|
|
|
|
| Properties | |
| ZnBr2 | |
| Molar mass | 225.198 g/mol |
| Appearance | white crystalline powder hygroscopic |
| Density | 4.20 g/cm3 (20 °C) 4.22 g/cm3 (25 °C) |
| Melting point | 394 °C (741 °F; 667 K) |
| Boiling point | 697 °C (1,287 °F; 970 K) |
| 311 g/100 mL (0 °C) 447 g/100 mL (20 °C) 538 g/100 mL (100 °C) |
|
| Solubility | very soluble in alcohol, ether, acetone, tetrahydrofuran |
|
Refractive index (nD)
|
1.5452 |
| Hazards | |
| Safety data sheet | External MSDS |
| NFPA 704 | |
| Flash point | Non-flammable |
| Related compounds | |
|
Other anions
|
Zinc fluoride, Zinc chloride, Zinc iodide |
|
Other cations
|
Cadmium bromide, Mercury(II) bromide, Calcium bromide |
|
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
|
|
 (what is   ?) |
|
| Infobox references | |
Zinc bromide (ZnBr2) is an inorganic compound with the chemical formula ZnBr2. It is a colourless salt that shares many properties with zinc chloride (ZnCl2), namely a high solubility in water forming acidic solutions, and solubility in organic solvents. It is hygroscopic and forms a dihydrate ZnBr2 · 2H2O.
ZnBr2 · 2H2O is prepared by treating zinc oxide or zinc metal with hydrobromic acid.
The anhydrous material can be produced by dehydration of the dihydrate with hot CO2 or by reaction of zinc metal and bromine.
Crystalline ZnBr2 adopts the same structure as ZnI2: four tetrahedral Zn centers share three vertices to form “super-tetrahedra” of nominal composition {Zn4Br10}2−, which are linked by their vertices to form a three-dimensional structure. The dihydrate ZnBr2 · 2H2O also has a usual structure and should be described as Zn(H2O)6 Zn2Br6, where the Zn2Br62− ion has bromine bridges linking the two zinc atoms. A similar structure is found in the dimeric form of aluminium bromide (Al2Br6).
Gaseous ZnBr2 is linear in accordance with VSEPR theory with a Zn-Br bond length of 221 pm.
Zinc bromide is used in the following applications:
Safety considerations are similar to those for zinc chloride, for which the toxic dose for humans is 3–5 g.
...
Wikipedia