Silver carbonate is the

chemical compound A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) containing atoms from more than one chemical element held together by chemical bonds. A molecule consisting of atoms of only one element ...

with the formula Ag₂CO₃. This salt is yellow but typical samples are grayish due to the presence of elemental

silver Silver is a chemical element with the symbol Ag (from the Latin ', derived from the Proto-Indo-European ''h₂erǵ'': "shiny" or "white") and atomic number 47. A soft, white, lustrous transition metal, it exhibits the highest electrical ...

. It is poorly soluble in water, like most

transition metal In chemistry, a transition metal (or transition element) is a chemical element in the d-block of the periodic table (groups 3 to 12), though the elements of group 12 (and less often group 3) are sometimes excluded. They are the elements that ca ...

carbonate A carbonate is a salt of carbonic acid (H2CO3), characterized by the presence of the carbonate ion, a polyatomic ion with the formula . The word ''carbonate'' may also refer to a carbonate ester, an organic compound containing the carbonate ...

Preparation and reactions

Silver carbonate can be prepared by combining aqueous solutions of sodium carbonate with a deficiency of

silver nitrate Silver nitrate is an inorganic compound with chemical formula . It is a versatile precursor to many other silver compounds, such as those used in photography. It is far less sensitive to light than the halides. It was once called ''lunar causti ...

. :2 AgNO3(aq) + Na2CO3(aq) -> Ag2CO3(s) + 2 NaNO3(aq) Freshly prepared silver carbonate is colourless, but the solid quickly turns yellow. Silver carbonate reacts with ammonia to give the diamminesilver(I) ( g(NH₃)₂sup>+)

complex ion A coordination complex consists of a central atom or ion, which is usually metallic and is called the ''coordination centre'', and a surrounding array of bound molecules or ions, that are in turn known as ''ligands'' or complexing agents. Many ...

. Like other diamminesilver(I) solutions, including Tollen's reagent, there is a possibility that explosive

Silver nitride Silver nitride is an explosive chemical compound with symbol Ag3N. It is a black, metallic-looking solid which is formed when silver oxide or silver nitrate, is dissolved in concentrated solutions of ammonia, causing formation of the diammine silve ...

may precipitate out of the solution. Silver nitride was previously known as fulminating silver but due to confusions with silver fulminate it has been discontinued by the

IUPAC The International Union of Pure and Applied Chemistry (IUPAC ) is an international federation of National Adhering Organizations working for the advancement of the chemical sciences, especially by developing nomenclature and terminology. It is ...

. With hydrofluoric acid, it gives silver fluoride. The thermal conversion of silver carbonate to silver metal proceeds via formation of silver oxide: :Ag2CO3 -> Ag2O + CO2 :2 Ag2O ->4 Ag + O2

Uses

The principal use of silver carbonate is for the production of silver powder for use in microelectronics. It is reduced with

formaldehyde Formaldehyde ( , ) (systematic name methanal) is a naturally occurring organic compound with the formula and structure . The pure compound is a pungent, colourless gas that polymerises spontaneously into paraformaldehyde (refer to section ...

, producing silver free of alkali metals:Andreas Brumby et al. "Silver, Silver Compounds, and Silver Alloys" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2008. :Ag2CO3 + CH2O -> 2 Ag + 2 CO2 + H2O Silver carbonate is used as a reagent in organic synthesis such as the Koenigs-Knorr reaction. In the Fétizon oxidation, silver carbonate on

celite Diatomaceous earth (), diatomite (), or kieselgur/kieselguhr is a naturally occurring, soft, siliceous sedimentary rock that can be crumbled into a fine white to off-white powder. It has a particle size ranging from more than 3 μm to les ...

serves as an

oxidising agent An oxidizing agent (also known as an oxidant, oxidizer, electron recipient, or electron acceptor) is a substance in a redox chemical reaction that gains or " accepts"/"receives" an electron from a (called the , , or ). In other words, an oxid ...

to form

lactone Lactones are cyclic carboxylic esters, containing a 1-oxacycloalkan-2-one structure (), or analogues having unsaturation or heteroatoms replacing one or more carbon atoms of the ring. Lactones are formed by intramolecular esterification of the co ...

s from diols. It is also employed to convert alkyl bromides into alcohols. As a base, it has been used in the

Wittig reaction The Wittig reaction or Wittig olefination is a chemical reaction of an aldehyde or ketone with a triphenyl phosphonium ylide called a Wittig reagent. Wittig reactions are most commonly used to convert aldehydes and ketones to alkenes. Mos ...

. and in C-H bond activation. J. Org. Chem., 2018, 83 (16), pp 9312–9321 https://doi.org/10.1021/acs.joc.8b01284.

References

External links

{{Silver compounds Silver compounds Carbonates