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| Names | |
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| IUPAC name Ammonium bromide | |
| Identifiers | |
3D model (JSmol) | |
| ChEBI | |
| ChemSpider |
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| ECHA InfoCard | 100.031.973 |
| EC Number |
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| RTECS number |
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| UNII | |
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| Properties | |
| NH4Br | |
| Molar mass | 97.94 g/mol |
| Appearance | white powder,hygroscopic |
| Density | 2.429 g/cm3 |
| Melting point | 235 °C (455 °F; 508 K) |
| Boiling point | 452 °C (846 °F; 725 K) |
| 60.6 g/100 mL (0 °C) 78.3 g/100 mL (25 °C) 145 g/100 mL (100 °C) | |
| −47.0×10−6 cm3/mol | |
Refractive index (nD) | 1.712 |
| Structure | |
| Isometric | |
| Hazards | |
| GHS labelling: | |
 [1] | |
| Warning | |
| H315,H319,H335[1] | |
| P261,P264,P271,P280,P302+P352,P304+P340,P305+P351+P338,P312,P321,P332+P313,P337+P313,P362,P403+P233,P405,P501 | |
| NFPA 704 (fire diamond) | |
| Related compounds | |
Otheranions | Ammonium fluoride Ammonium chloride Ammonium iodide |
Othercations | Sodium bromide Potassium bromide |
Except where otherwise noted, data are given for materials in theirstandard state (at 25 °C [77 °F], 100 kPa). | |
Ammonium bromide, NH4Br, is theammonium salt ofhydrobromic acid. The chemical crystallizes in colorless prisms, possessing asaline taste; it sublimes on heating and is easily soluble in water. On exposure to air it gradually assumes a yellow color because of the oxidation ofbromide (Br−) tobromine (Br2).
Ammonium bromide can be prepared by the direct action ofhydrogen bromide onammonia.
It can also be prepared by the reaction of ammonia withiron(II) bromide oriron(III) bromide, which may be obtained by passing aqueous bromine solution over iron filings.
Ammonium bromide is a weak acid with apKa of approximately 9 in water. It is anacid salt because theammonium ionhydrolyzes slightly in water.
Ammonium bromide is a strong electrolyte when put in water:
Ammonium bromide decomposes to ammonia andhydrogen bromide when heated at elevated temperatures:
Ammonium bromide is used for photography infilms, plates andpapers; in fireproofing of wood; inlithography and process engraving; in corrosion inhibitors; and in pharmaceutical preparations.[2]
