Silver chloride

Jump to: navigation, search
Template:Chembox E numberTemplate:Chembox SolubilityInWater
Silver chloride
IUPAC name Silver(I) chloride
Other names Silver chloride; cerargyrite; chlorargyrite; horn silver
Identifiers
ECHA InfoCard Lua error in Module:Wikidata at line 879: attempt to index field 'wikibase' (a nil value). Lua error in Module:Wikidata at line 879: attempt to index field 'wikibase' (a nil value).
RTECS number VW3563000
Properties
AgCl
Molar mass 143.321 g mol−1
Appearance White Solid
Density 5.56 × 103 kg m−3
Melting point
Boiling point
Structure
Crystal structure halite
Thermochemistry
Std enthalpy of
formation
ΔfHo298
−127.01 kJ mol−1
Standard molar
entropy
So298
96.25 J mol−1 K−1
Hazards
Related compounds
Other anions {{{value}}}
Except where noted otherwise, data are given for
materials in their standard state
(at 25 °C, 100 kPa)

Infobox disclaimer and references

Silver chloride is a chemical compound with the chemical formula AgCl. This white crystalline solid is well known for its low solubility in water (this behavior being reminiscent of the chlorides of Tl+ and Pb2+). Upon illumination or heating, silver chloride converts to silver (and chlorine), which is signalled by greyish or purplish coloration to some samples. AgCl occurs naturally as a mineral chlorargyrite.

Coordination chemistry

The solid adopts the fcc NaCl structure, in which each Ag+ ion is surrounded by an octahedron of six chloride ligands. AgF and AgBr crystallize similarly.[1] AgCl dissolves in solutions containing ligands such as chloride, triphenylphosphine, thiosulfate, and ammonia. Silver chloride reacts with these ligands according to the following illustrative equations:

AgCl(s) + Cl(concentrated, aqueous) → AgCl2-(aq)
AgCl(s) + 2S2O32–(aq) → Ag[(S2O3)2]3-(aq) + Cl-(aq)
AgCl(s) + 2NH3(aq) → Ag[(NH3)2]+(aq) + Cl-(aq)

Most complexes derived from AgCl are two-, three-, and, in rare cases, four-coordinate, adopting linear, trigonal planar, and tetrahedral coordination geometries, respectively.

In one of the most famous reactions in chemistry, addition of aqueous silver nitrate to an equally colourless solution of sodium chloride produces an opaque white precipitate of AgCl:[2]

Ag+(aq) + Cl-(aq) → AgCl(s)

This conversion is a common test for the presence of chloride in solution. The solubility product, Ksp, for AgCl is 1.8 x 10-10, which indicates that one liter of water will dissolve 0.000013 grams of AgCl. The chloride content of an aqueous solution can be determined quantitatively by weighing the precipitated AgCl, which conveniently is non-hygroscopic since AgCl is one of the few transition metal chlorides that is unreactive toward water. Ions that interfere with this test are bromide and iodide, as well as a variety of ligand. For AgBr and AgI, the values are 5.2 x 10-13 and 8.3 x 10-17, respectively. The bromide (tan) and iodide (yellow) are also significantly more photosensitive than is AgCl.

Applications

Footnotes

  1. Wells, A.F. (1984) Structural Inorganic Chemistry, Oxford: Clarendon Press. ISBN 0-19-855370-6.
  2. More info on Chlorine test: [1]

External links

de:Silberchlorid it:Cloruro d'argento hu:Ezüst-klorid nl:Zilverchloride nn:Sølvklorid sv:Silverklorid



Linked-in.jpg