Silver oxide 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
In science, a formula is a concise way of expressing information symbolically, as in a mathematical formula or a ''chemical formula''. The informal use of the term ''formula'' in science refers to the general construct of a relationship betwe ...
Ag2 O. It is a fine black or dark brown powder that is used to prepare other
silver
Silver is a chemical element; it has Symbol (chemistry), symbol Ag () and atomic number 47. A soft, whitish-gray, lustrous transition metal, it exhibits the highest electrical conductivity, thermal conductivity, and reflectivity of any metal. ...
compounds.
Preparation
Silver oxide can be prepared by combining aqueous solutions of
silver nitrate and an
alkali hydroxide. This reaction does not afford appreciable amounts of silver hydroxide due to the favorable energetics for the following reaction:
:(
p''K'' = 2.875)
With suitably controlled conditions, this reaction can be used to prepare Ag
2O powder with properties suitable for several uses including as a fine grained conductive paste filler.
Structure and properties
Ag
2O features linear, two-coordinate Ag centers linked by tetrahedral oxides. It is
isostructural with
Cu2O. It "dissolves" in solvents that degrade it. It is slightly soluble in water due to the formation of the ion and possibly related hydrolysis products.
It is soluble in
ammonia
Ammonia is an inorganic chemical compound of nitrogen and hydrogen with the chemical formula, formula . A Binary compounds of hydrogen, stable binary hydride and the simplest pnictogen hydride, ammonia is a colourless gas with a distinctive pu ...
solution, producing active compound of
Tollens' reagent. A
slurry of Ag
2O is readily attacked by
acid
An acid is a molecule or ion capable of either donating a proton (i.e. Hydron, hydrogen cation, H+), known as a Brønsted–Lowry acid–base theory, Brønsted–Lowry acid, or forming a covalent bond with an electron pair, known as a Lewis ...
s:
:
where HX =
HF,
HCl,
HBr,
HI, or
CF3COOH. It will also react with solutions of alkali chlorides to precipitate
silver chloride, leaving a solution of the corresponding alkali hydroxide.
[General Chemistry by ]Linus Pauling
Linus Carl Pauling ( ; February 28, 1901August 19, 1994) was an American chemist and peace activist. He published more than 1,200 papers and books, of which about 850 dealt with scientific topics. ''New Scientist'' called him one of the 20 gre ...
, 1970 Dover ed. p703-704
Despite the photosensitivity of many silver compounds, silver oxide is not photosensitive, although it readily decomposes at temperatures above 280 °C.
[Merck Index of Chemicals and Drugs](_blank)
, 14th ed. monograph 8521
Applications
This oxide is used in
silver-oxide batteries. In organic chemistry, silver oxide is used as a mild
oxidizing agent. For example, it oxidizes
aldehydes to
carboxylic acid
In organic chemistry, a carboxylic acid is an organic acid that contains a carboxyl group () attached to an Substituent, R-group. The general formula of a carboxylic acid is often written as or , sometimes as with R referring to an organyl ...
s.
References
External links
Annealing of Silver Oxide– Demonstration experiment: Instruction and video
{{Silver compounds
Silver compounds
Transition metal oxides