Chromium(III) nitrate describes several

inorganic compound In chemistry, an inorganic compound is typically a chemical compound that lacks carbon–hydrogen bonds, that is, a compound that is not an organic compound. The study of inorganic compounds is a subfield of chemistry known as '' inorganic chemist ...

s consisting of chromium, nitrate and varying amounts of water. Most common is the dark violet hygroscopic solid. An

anhydrous A substance is anhydrous if it contains no water. Many processes in chemistry can be impeded by the presence of water; therefore, it is important that water-free reagents and techniques are used. In practice, however, it is very difficult to achie ...

green form is also known. Chromium(III) nitrate compounds are of a limited commercial importance, finding some applications in the dyeing industry. It is common in academic laboratories for the synthesis of chromium

coordination complex A coordination complex consists of a central atom or ion, which is usually metallic and is called the ''coordination centre'', and a surrounding array of bound molecules or ions, that are in turn known as ''ligands'' or complexing agents. Many ...

es.

Structure

The relatively complicated

formula In science, a formula is a concise way of expressing information symbolically, as in a mathematical formula or a ''chemical formula''. The informal use of the term ''formula'' in science refers to the general construct of a relationship betwee ...

- r(H₂O)₆NO₃)₃• 3H₂O - betray a simple structure of this material. The chromium centers are bound to six

aquo ligand In chemistry, metal aquo complexes are coordination compounds containing metal ions with only water as a ligand. These complexes are the predominant species in aqueous solutions of many metal salts, such as metal nitrates, sulfates, and perchlorat ...

s, and the remaining volume of the solid is occupied by three nitrate anions and three molecules of water of crystallization.

Properties and preparation

The

salt forms green crystals and is very soluble in water (in contrast to anhydrous

chromium(III) chloride Chromium(III) chloride (also called chromic chloride) describes any of several chemical compounds with the formula CrCl3, where can be 0, 5, and 6. The anhydrous compound with the formula CrCl3 is a violet solid. The most common form of the tri ...

which dissolves very slowly except under special conditions). At 100 °C it decomposes. The red-violet hydrate is highly soluble in water. Chromium nitrate is used in the production of

alkali metal The alkali metals consist of the chemical elements lithium (Li), sodium (Na), potassium (K),The symbols Na and K for sodium and potassium are derived from their Latin names, ''natrium'' and ''kalium''; these are still the origins of the names ...

-free

catalyst Catalysis () is the process of increasing the rate of a chemical reaction by adding a substance known as a catalyst (). Catalysts are not consumed in the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recyc ...

s and in

pickling Pickling is the process of preserving or extending the shelf life of food by either anaerobic fermentation in brine or immersion in vinegar. The pickling procedure typically affects the food's texture and flavor. The resulting food is called a ...

. Chromium nitrate can be prepared by dissolving

chromium oxide Chromium oxide may refer to: * Chromium(II) oxide, CrO * Chromium(III) oxide, Cr2O3 * Chromium dioxide (chromium(IV) oxide), CrO2, which includes the hypothetical compound chromium(II) chromate * Chromium trioxide (chromium(VI) oxide), CrO3 * Chro ...

nitric acid Nitric acid is the inorganic compound with the formula . It is a highly corrosive mineral acid. The compound is colorless, but older samples tend to be yellow cast due to decomposition into oxides of nitrogen. Most commercially available nitri ...

References

{{nitrates Chromium(III) compounds Nitrates