Mercury(I) nitrate is a
inorganic compound
In chemistry, an inorganic compound is typically a chemical compound that lacks carbon–hydrogen bonds, that is, a compound that is not an organic compound. The study of inorganic compounds is a subfield of chemistry known as '' inorganic chemist ...
, a salt of mercury and nitric acid with the formula Hg
2(NO
3)
2. A yellow solid, the compound is used as a precursor to other complexes of Hg
22+ complexes.The structure of the hydrate has been determined by
X-ray crystallography
X-ray crystallography is the experimental science determining the atomic and molecular structure of a crystal, in which the crystalline structure causes a beam of incident X-rays to diffract into many specific directions. By measuring the angles ...
. It consists of a
2O-Hg-Hg-OH2sup>2+ center, with a Hg-Hg distance of 254 pm.
Reactions
Mercury(I) nitrate is formed when elemental mercury is combined with ''dilute''
nitric acid
Nitric acid is the inorganic compound with the formula . It is a highly corrosive mineral acid. The compound is colorless, but older samples tend to be yellow cast due to decomposition into oxides of nitrogen. Most commercially available nitri ...
(concentrated nitric acid will yield
mercury(II) nitrate
Mercury(II) nitrate is an inorganic compound with the formula Hg(NO3)2.xH2O. These colorless or white soluble crystalline salts are occasionally used as a reagent. It is made by treating mercury with hot concentrated nitric acid. Neither anhydr ...
). Mercury(I) nitrate is a
reducing agent
In chemistry, a reducing agent (also known as a reductant, reducer, or electron donor) is a chemical species that "donates" an electron to an (called the , , , or ).
Examples of substances that are commonly reducing agents include the Earth meta ...
which is
oxidized
Redox (reduction–oxidation, , ) is a type of chemical reaction in which the oxidation states of substrate change. Oxidation is the loss of electrons or an increase in the oxidation state, while reduction is the gain of electrons or a d ...
upon contact with air.
Mercuric nitrate reacts with elemental mercury to form mercurous nitrate.
Solutions of mercury(I) nitrate are
acid
In computer science, ACID ( atomicity, consistency, isolation, durability) is a set of properties of database transactions intended to guarantee data validity despite errors, power failures, and other mishaps. In the context of databases, a sequ ...
ic due to slow reaction with water:
:Hg
2(NO
3)
2 + H
2O ⇌ Hg
2(NO
3)(OH) + HNO
3
Hg
2(NO
3)(OH) forms a yellow
precipitate
In an aqueous solution, precipitation is the process of transforming a dissolved substance into an insoluble solid from a super-saturated solution. The solid formed is called the precipitate. In case of an inorganic chemical reaction leading ...
.
If the solution is boiled or exposed to light, mercury(I) nitrate undergoes a
disproportionation
In chemistry, disproportionation, sometimes called dismutation, is a redox reaction in which one compound of intermediate oxidation state converts to two compounds, one of higher and one of lower oxidation states. More generally, the term can b ...
reaction yielding elemental mercury and mercury(II) nitrate:
[
]
:Hg
2(NO
3)
2 ⇌ Hg + Hg(NO
3)
2
These reactions are reversible; the nitric acid formed can redissolve the basic salt.
References
Mercury(I) compounds
Nitrates
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