Silver chloride

chembox new
ImageFile = Silver-chloride-3D-ionic.png ImageSize =
IUPACName = Silver(I) chloride
OtherNames = Silver chloride; cerargyrite; chlorargyrite; horn silver
Section1 = Chembox Identifiers
Abbreviations =
CASNo = 7783-90-6
EINECS =
PubChem =
SMILES =
InChI =
RTECS = VW3563000
MeSHName =
ChEBI =
KEGG =
ATCCode_prefix =
ATCCode_suffix =
ATC_Supplemental =
Section2 = Chembox Properties
Ag=1 | Cl=1
MolarMass = 143.321 g mol⁻¹
Appearance = White Solid
Density = 5.56 × 10³ kg m⁻³
MeltingPt = 455 °C
Melting_notes =
BoilingPt = 1550 °C
Boiling_notes =
Solubility = 52 × 10⁻⁶ g/100 g at 50 °C
SolubleOther =
Solvent = water
pKa =
pKb =
Section3 = Chembox Structure
CrystalStruct = halite
Coordination =
MolShape =
Section4 = Chembox Thermochemistry
DeltaHf = −127.01 kJ mol⁻¹
DeltaHc =
Entropy = 96.25 J mol⁻¹ K⁻¹
HeatCapacity =
Section5 = Chembox Pharmacology
AdminRoutes =
Bioavail =
Metabolism =
HalfLife =
ProteinBound =
Excretion =
Legal_status =
Legal_US =
Legal_UK =
Legal_AU =
Legal_CA =
PregCat =
PregCat_AU =
PregCat_US =
Section6 = Chembox Explosive
ShockSens =
FrictionSens =
ExplosiveV =
REFactor =
Section7 = Chembox Hazards
ExternalMSDS = [http://sciencelab.com/msds.php?msdsId=9927255 ScienceLab.com]
ExternalMSDS = [http://www.saltlakemetals.com/MSDS_Silver_Chloride.htm Salt Lake Metals]
EUClass =
EUIndex =
MainHazards =
NFPA-H = 2
NFPA-F = 0
NFPA-R = 0
NFPA-O =
RPhrases =
SPhrases =
RSPhrases =
FlashPt =
Autoignition =
ExploLimits =
PEL =
Section8 = Chembox Related
OtherAnions = silver(I) fluoride, silver bromide, silver iodide
OtherCations =
OtherFunctn =
Function =
OtherCpds =

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. [Wells, A.F. (1984) Structural Inorganic Chemistry, Oxford: Clarendon Press. ISBN 0-19-855370-6.] However, the crystallography depends on the condition of crystallization, primarily free silver ion concentration. AgCl dissolves in solutions containing ligands such as chloride, cyanide, triphenylphosphine, thiosulfate, thiocyanate and ammonia. Silver chloride reacts with these ligands according to the following illustrative equations::AgCl(s) + Cl⁻(aq) → 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 colorless aqueous silver nitrate to an equally colorless solution of sodium chloride produces an opaque white precipitate of AgCl: [More info on Chlorine test: [http://www.epa.gov/sw-846/pdfs/9076.pdf] ] :Ag⁺(aq) + Cl⁻(aq) → AgCl(s)This conversion is a common test for the presence of chloride in solution. The solubility product, "K"_sp, 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 ligands (see silver halide). For AgBr and AgI, the "K"_sp values are 5.2 x 10⁻¹³ and 8.3 x 10⁻¹⁷, respectively. The silver bromide (slightly yellowish white) and silver iodide (pale yellow) are also significantly more photosensitive than is AgCl.

Applications

*Silver chloride is used to make photographic paper since it reacts with photons to form latent image and via photoreduction.
*The Silver Chloride Electrode is a common reference electrode in electrochemistry.
*Silver chloride's low solubility makes it a useful addition to pottery glazes for the production of "Inglaze lustre".
*Silver chloride has been used as an antidote for mercury poisoning, assisting in the elimination of mercury.
*Silver chloride is often used in photochromic lenses, again taking advantage of its reversible conversion to Ag metal.
*Silver chloride is used to create yellow, amber, and brown shades in stained glass manufacture.
*Silver chloride is used in bandages and wound healing products.

Footnotes

External links

* [http://www.crystran.co.uk/products.asp?productid=56 Silver Chloride Data Sheet]
*Science Lab.com [http://sciencelab.com/msds.php?msdsId=9927255 MSDS for silver chloride]
*Salt Lake Metals.com [http://www.saltlakemetals.com/MSDS_Silver_Chloride.htm MSDS for Silver Chloride]
*Solubility of [http://www.saltlakemetals.com/Solubility_of_Silver_Chloride.htm Silver Chloride] in various solutions - plus Lab Notes