Silver(I) fluoride
| Names | |
|---|---|
| IUPAC name
Silver(I) fluoride
| |
| Properties | |
| AgF | |
| Molar mass | 126.8666 g/mol |
| Appearance | Yellow-brown solid (anhydrous) Colorless solid (hydrated) |
| Odor | Odorless |
| Density | 5.852 g/cm3 (15 °C) |
| Melting point | 435 °C (815 °F; 708 K) |
| Boiling point | 1,159 °C (2,118 °F; 1,432 K) |
| 85.78 g/100 ml (0 °C) 119.8 g/100 ml (10 °C) 179.1 g/100 ml (25 °C) 213.4 g/100 ml (50 °C) | |
| Solubility | Soluble in acetonitrile Poorly soluble in ethanol, methanol Insoluble in hydrocarbons |
| Solubility in bromine fluoride | 3.33 g/100 g (25 °C) 4.25 g/100 g (70 °C) |
| Solubility in hydrogen fluoride | 83 g/100 g (12 °C) |
| Solubility in methanol | 1.5 g/100 ml (25 °C) |
| Vapor pressure | ~0 mmHg |
| Thermochemistry | |
| Std molar
entropy (S |
83.7 J·K-1·mol-1 |
| Std enthalpy of
formation (ΔfH |
-206 kJ/mol |
| Hazards | |
| Safety data sheet | Sigma-Aldrich |
| Flash point | Non-flammable |
| Related compounds | |
| Related compounds
|
Silver chloride Silver bromide 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(I) fluoride (or just silver fluoride) is the inorganic compound with the formula AgF.
It is one of the three main fluorides of silver, the others being silver subfluoride and silver(II) fluoride. However, since silver(I) fluoride is more commonly encountered as it's easier to synthesize, the term "silver fluoride" most often refers to the Ag(I) compound.
Contents
Properties
Chemical
In contrast with the other silver halides, anhydrous silver(I) fluoride is not appreciably photosensitive, although the dihydrate is.
Physical
Silver(I) oxide is a chemical compound, which can be colorless (hydrated) or yellow (anhydrous). Unlike the other silver halides, it is very soluble in water. It is also soluble in many other solvents, like acetonitrile.
It is also unique among silver(I) compounds and the silver halides in that it forms the hydrates AgF.(H2O)2 and AgF.(H2O)4 on precipitation from aqueous solution.
Availability
Silver(I) fluoride is sold by lab suppliers, though it's not cheap.
Preparation
Silver(I) fluoride can be produced by adding hydrofluoric acid to silver carbonate or silver(I) oxide, in a PE or PTFE beaker or flask.
- Ag2CO3 + 2 HF → 2 AgF + H2O + CO2
- Ag2O + 2 HF → 2 AgF + H2O
The silver fluoride is precipitated out of the resulting solution by adding acetone.
High-purity silver(I) fluoride can be produced by the heating of silver carbonate to 310 °C under a hydrogen fluoride environment, in a platinum tube.
Laboratory routes to the compound typically avoid the use of hydrogen fluoride/hydrofluoric acid, due to its hazards. One method is the thermal decomposition of silver tetrafluoroborate:
- AgBF4 → AgF + BF3
Projects
- Fluorinating agent
- Make fluorocarbons
- Synthesis of silver diamine fluoride
Handling
Safety
Silver fluoride will release HF in contact with a strong acid, which is hazardous.
Storage
In closed plastic or amber glass.
Disposal
Since silver is expensive, it's best to recycle it.
