Mercury(I) nitrate is an inorganic compound, a salt of mercury and nitric acid with the formula Hg2(NO3)2. A yellow solid, the compound is used as a precursor to other Hg22+ complexes. The structure of the hydrate has been determined by X-ray crystallography. It consists of a [H2O-Hg-Hg-OH2]2+ center, with a Hg-Hg distance of 254 pm.
3D model (JSmol)
CompTox Dashboard (EPA)
|Molar mass||525.19 g/mol (anhydrous)|
561.22 g/mol (dihydrate)
|Appearance||white monoclinic crystals (anhydrous)|
colorless crystals (dihydrate)
|Density||? g/cm3 (anhydrous)|
4.8 g/cm3 (dihydrate)
|Melting point||? (anhydrous)|
decomposes at 70 °C (dihydrate)
|slightly soluble, reacts|
|NFPA 704 (fire diamond)|
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
(what is ?)
Mercury(I) nitrate is formed when elemental mercury is combined with dilute nitric acid (concentrated nitric acid will yield mercury(II) nitrate). Mercury(I) nitrate is a reducing agent which is oxidized upon contact with air.
Mercuric nitrate reacts with elemental mercury to form mercurous nitrate.
Solutions of mercury(I) nitrate are acidic due to slow reaction with water:
Hg2(NO3)(OH) forms a yellow precipitate.
These reactions are reversible; the nitric acid formed can redissolve the basic salt.