Mercury(I) nitrate

Mercury(I) nitrate is a chemical compound with the formula Hg2(NO3)2. It was first discovered by Prafulla Chandra Ray It is used in the preparation of other mercury(I) compounds, and 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.
Mercuric nitrate can be reacted 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.
If the solution is boiled or exposed to light, mercury(I) nitrate undergoes a disproportionation reaction yielding elemental mercury and mercury(II) nitrate:
These reactions are reversible; the nitric acid formed can redissolve the basic salt.