Mercury(I) nitrate

Mercury(I) nitrate[1][2]
IUPAC name Mercury(I) nitrate
Other names Mercurous nitrate
Identifiers
CAS number	10415-75-5, (anhydrous) [7782-86-7] (dihydrate)
Properties
Molecular formula	Hg2(NO3)2 (anhydrous) Hg2(NO3)2·2H2O (dihydrate)
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)
Solubility in water	slightly soluble, reacts
Hazards
NFPA 704	1 3 1 OX
Related compounds
Other anions	Mercury(I) fluoride Mercury(I) chloride Mercury(I) bromide Mercury(I) iodide
Other cations	Mercury(II) nitrate
Y nitrate (verify) (what is: Y/N?) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Mercury(I) nitrate is a chemical compound with the formula Hg₂(NO₃)₂. It is used in the preparation of other mercury(I) compounds, and, like all other mercury compounds, it is toxic.

Reactions

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.

Solutions of mercury(I) nitrate are acidic due to slow reaction with water:

Hg₂(NO₃)₂ + H₂O → Hg₂(NO₃)(OH) + HNO₃

Hg₂(NO₃)(OH) forms a yellow precipitate.

If the solution is boiled or exposed to light, mercury(I) nitrate undergoes a disproportionation reaction yielding elemental mercury and mercury(II) nitrate^[2]:

2Hg₂(NO₃)₂ → Hg + Hg(NO₃)₂

References

1. ^ Lide, David R. (1998), Handbook of Chemistry and Physics (87 ed.), Boca Raton, FL: CRC Press, pp. 4–45, ISBN 0849305942 
2. ^ ^{a b} Patnaik, Pradyot (2003), Handbook of Inorganic Chemical Compounds, McGraw-Hill Professional, pp. 573, ISBN 0070494398, http://books.google.com/?id=Xqj-TTzkvTEC&pg=PA552&dq=%22Manganese%28II%29+acetate%22, retrieved 2009-07-20