Cadmium nitrate describes any of a related members of a family of inorganic compound

Inorganic compound

Inorganic compounds have traditionally been considered to be of inanimate, non-biological origin. In contrast, organic compounds have an explicit biological origin. However, over the past century, the classification of inorganic vs organic compounds has become less important to scientists,...

 with the general formula

Chemical formula

A chemical formula or molecular formula is a way of expressing information about the atoms that constitute a particular chemical compound....

 Cd(NO₃)₂.xH₂O. The anhydrous form is volatile but the others are salts. All are colourless crystalline solids that absorb moisture from air and becomes watery, that is deliquescent. Cadmium compounds are also known to be carcinogenic.

Uses

Cadmium nitrate is used for coloring glass

Glass

Glass is an amorphous solid material. Glasses are typically brittle and optically transparent.The most familiar type of glass, used for centuries in windows and drinking vessels, is soda-lime glass, composed of about 75% silica plus Na2O, CaO, and several minor additives...

 and porcelain

Porcelain

Porcelain is a ceramic material made by heating raw materials, generally including clay in the form of kaolin, in a kiln to temperatures between and...

 and as a flash powder

Flash powder

Flash powder is a pyrotechnic composition, a mixture of oxidizer and metallic fuel, which burns quickly and if confined produces a loud report. It is widely used in theatrical pyrotechnics and fireworks and was once used for flashes in photography.Different varieties of flash powder are made from...

 in photography

Photography

Photography is the art, science and practice of creating durable images by recording light or other electromagnetic radiation, either electronically by means of an image sensor or chemically by means of a light-sensitive material such as photographic film...

.

Preparation

Cadmium nitrate is prepared by dissolving cadmium metal or its oxide, hydroxide, or carbonate, in nitric acid

Nitric acid

Nitric acid , also known as aqua fortis and spirit of nitre, is a highly corrosive and toxic strong acid.Colorless when pure, older samples tend to acquire a yellow cast due to the accumulation of oxides of nitrogen. If the solution contains more than 86% nitric acid, it is referred to as fuming...

 followed by crystallization

Crystallization

Crystallization is the process of formation of solid crystals precipitating from a solution, melt or more rarely deposited directly from a gas. Crystallization is also a chemical solid–liquid separation technique, in which mass transfer of a solute from the liquid solution to a pure solid...

:

CdO + 2HNO₃ → Cd(NO₃)₂ + H₂O

CdCO₃ + 2 HNO₃ → Cd(NO₃)₂ + CO₂ + H₂O

Cd + 4 HNO₃ → 2 NO₂ + 2 H₂O + Cd(NO₃)₂

Reactions

Thermal dissociation at elevated temperatures produces cadmium oxide

Cadmium oxide

Cadmium oxide is an inorganic compound with the formula CdO. It is one of the main precursors to other cadmium compounds. It crystallizes in a cubic rocksalt lattice like sodium chloride, with octahedral cation and anion centers. It occurs naturally as the rare mineral monteponite. Cadmium oxide...

 and oxides of nitrogen. When hydrogen sulfide

Hydrogen sulfide

Hydrogen sulfide is the chemical compound with the formula . It is a colorless, very poisonous, flammable gas with the characteristic foul odor of expired eggs perceptible at concentrations as low as 0.00047 parts per million...

 is passed through an acidified solution of cadmium nitrate, yellow cadmium sulfide

Cadmium sulfide

Cadmium sulfide is the inorganic compound with the formula CdS. Cadmium sulfide is a yellow solid. It occurs in nature with two different crystal structures as the rare minerals greenockite and hawleyite, but is more prevalent as an impurity substituent in the similarly structured zinc ores...

 is formed. A red modification of the sulfide is formed under boiling conditions.

When with caustic soda solution, cadmium oxide forms precipitate of cadmium hydroxide

Cadmium hydroxide

Cadmium hydroxide is an inorganic compound with the formula Cd2. It is a white crystalline ionic compound that is a key component of NiCd batteries.-Preparation and reactions:...

. Many insoluble cadmium salts are obtained by such precipitation reactions.