Chromium(III) phosphate
Chromium(III) phosphate (CrPO4) is an inorganic compound. It is a phosphate salt of chromium in the +3 oxidation state. It exists as a solid, typically a green or violet powder, although hydrated forms may exhibit different colors.
Chromium(III) phosphate is generally insoluble in water but may dissolve in acidic solutions. It is often used as a pigment, corrosion inhibitor, and in the surface treatment of metals. It can also be used as a catalyst in certain chemical reactions.
The hydrated forms of chromium(III) phosphate are more common. These hydrated compounds are generally amorphous solids and their precise chemical formula can vary depending on the degree of hydration. The anhydrous form is more difficult to obtain and requires specific dehydration procedures.
The compound can be prepared by reacting a soluble chromium(III) salt with a phosphate salt, resulting in the precipitation of chromium(III) phosphate. The specific properties of the resulting compound can be influenced by the reaction conditions, such as pH, temperature, and the presence of other ions.