Chromium Sulfate (II) refers to an inorganic compound with the chemical formula CrSO4 · n H2O. In its pentahydrate form it is a blue colored solid that dissolves easily in water. A solution of the chromium (II) cation is easily oxidized by air to Cr (III). The solutions of Cr (II) are used in particular to reduce valuable agents in organic synthesis.
Salt is produced by treating chromium metal with diluted Sulfuric Acid according to: Cr + H2SO4 + 5 H2O → CrSO4·5 H2O + H2 Structure
In aqueous solutions, it forms complexes, presumably with six water molecules as ligands. The structures of the crystalline salts are similar to the corresponding hydrates of copper sulfate pentahydrate, trihydrate, monohydrate, and anhydrous. In all of these compounds, the Cr (II) in the center adopts an octahedral coordination geometry, being coordinated to six oxygens, provided with a combination of water and the sulphate ligands.
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