Chemical Properties
The monohydrate is a white crystalline or powdery substance; density 4.3g/cm3; decomposes on heating; soluble in water and nitric acid; insoluble in alcohol.
It is stable and hygroscopic. Mercuric nitrate is incompatible with mercuric nitrate in contact with organic materials, powdered metals, petroleum hydrocarbons, hypophosphoric acid, unsaturates, and aromatics, which react violently.
Uses
Mercury(II) nitrate is used in the preparation of other mercury compounds; in organic synthesis; and as an analytical standard for mercury.
Preparation
Mercury(II) nitrate is prepared by dissolving mercury in excess hot concentrated nitric acid. Upon evaporation of the solution, large colorless deliquescent crystals of monohydrate, Hg(NO3)2•H2O, form.
It also is obtained by boiling a solution of mercury(I) nitrate or by the action of light on mercury(I) nitrate:
Hg2(NO3)2 → Hg + 2HgNO3
Reactions
Gentle heating of mercury(II) nitrate gives mercury(II) oxide evolving nitrogen and oxygen:
Hg(NO3)2 → HgO + 2NO2 + ½ O2
However, on strong heating, mercury nitrate decomposes to mercury metal:
Hg(NO3)2 → Hg + 2NO2 + O2
When excess alkali hydroxide is added to a solution of mercury(II) nitrate, a yellow precipitate of HgO is obtained.
Addition of potassium thiocyanate solution forms a white precipitate of mercury(II) thiocyanate:
Hg2+ + 2SCN¯ → Hg(SCN)2
Addition of a small amount of alkali iodide to mercury(II) nitrate solution precipitates mercury(II) iodide:
Hg2+ + 2I¯ → HgI2
Similarly, mercury(II) cyanide precipitates upon the addition of potassium cyanide to mercury(II) nitrate solution:
Hg2+ + 2CN¯ → Hg(CN)2
Toxicity
Mercury(II) nitrate is highly toxic by ingestion and possibly other routes of exposure. The LD50 oral for the dihydrate in mouse is 25 mg/kg.
Chemical Properties
Mercuric nitrate is a white to yellowish crystalline solid with an odor like nitric acid. Normally exists
as the hemihydrate or the dihydrate
Uses
Mercury(II) nitrate is used as an oxidizing agent involved in organic synthesis. Its reaction with acetone yielded an organometallic compound containing mercury. In addition, it serves as a nitrification agent and analytical reagents used in the laboratory. It is involved in the preparation of mercury fulminate.
Potential Exposure
Mercuric nitrate is used in making
other chemicals; in felt manufacture and in making mercury
fulminate
Shipping
UN1625 Mercuric nitrate, Hazard Class: 6.1;
Labels: 6.1-Poisonous materials.
Purification Methods
Its solubility in H2O containing 1% HNO3 is 7.7%. Recrystallise it from a warm saturated solution of dilute HNO3 and cool to room temperature slowly to give elongated prisms. Rapid cooling gives plates. The colourless crystals should be stored in the dark. POISONOUS. [Grdenic J Chem Soc 1312 1956.]
Incompatibilities
A strong oxidizer. Reacts violently with
combustibles, petroleum hydrocarbons; reducing agents;
aldehydes, ammonia, ketones, phosphorus. Reacts with
acetylene, alcohol, phosphine, and sulfur to form shocksensitive compounds. Aqueous solution attacks most
metals. Vigorous and dangerous reaction with petroleum
hydrocarbons. Incompatible with organic materials;
acetylene, ethanol, phosphine, sulfur, hypophosphoric acid.
Inorganic mercury compounds are incompatible with acetylene, ammonia, chlorine dioxide; azides, calcium (amalgam
formation), sodium carbide; lithium, rubidium, copper.
Decomposes in heat or on exposure to light, producing
toxic fumes (mercury, nitrogen oxides)
