Silver bromide

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Silver bromide
Names
IUPAC name
Silver bromide
Other names
Argentous bromide
Bromargyrite
Bromyrite
Silver(I) bromide
Properties
AgBr
Molar mass 187.77 g/mol
Appearance Pale yellow solid
Odor Odorless
Density 6.473 g/cm3
Melting point 432 °C (810 °F; 705 K)
Boiling point 700 °C (1,292 °F; 973 K) (decomposes)
0.140 mg/l (20 °C)
Solubility Soluble in alkali cyanide solutions
Sparingly soluble in ammonia
Insoluble in alcohols
Solubility in ammonia 2.4 g/100 g (0 °C)[1]
Vapor pressure ~0 mmHg
Thermochemistry
107 J·mol−1·K−1
−100 kJ/mol
Hazards
Safety data sheet Fisher
Flash point Non-flammable
Related compounds
Related compounds
Silver(I) fluoride
Silver chloride
Silver iodide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Silver bromide is a soft, pale-yellow, light-sensitive water-insoluble salt, with the formula AgBr.

Properties

Chemical

Silver bromide reacts readily with liquid ammonia to generate a variety of ammine complexes, like Ag(NH
3
)
2
Br
and Ag(NH
3
)
2
Br
2
.

Silver bromide will slowly decompose when exposed to light into silver metal and bromine:

2 AgBr → 2 Ag + Br2

Physical

Silver bromide is a pale yellow solid, sensitive to light. It is insoluble in water and most solvents.

Availability

Silver bromide can be bought from chemical suppliers.

AgBr can be found naturally as the mineral bromargyrite.

Preparation

Silver bromide is extremely easy to prepare by metathesis reaction: a soluble bromide salt, like NaBr is added as solution to a solution of a soluble silver salt, such as silver nitrate. Due to its extremely low solubility, silver bromide will precipitate out of the solution, and can be filtered from the resulting suspension, washed and then dried.

AgNO3 + NaBr → NaNO3 + AgBr

Projects

  • Make photographic paper (photography)
  • Compound collecting

Handling

Safety

Silver bromide may be harmful if ingested in large amounts, but usually it doesn't pose a serious health risk. May cause silver stains though.

Storage

In closed amber glass or plastic bottles, away from light and reducing agents.

Disposal

Since silver is expensive, AgBr should be recycled. This can be done by reducing the compound to Ag metal, which is then collected and stored for further uses.

References

  1. Рабинович В.А., Хавин З.Я. Краткий химический справочник. - Л.: Химия, 1977 (Rabinovich V.A., Khavin Z.Ya. A short chemical reference book. - L .: Chemistry, 1977)

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