Potassium peroxochromate, potassium tetraperoxochromate(V), or simply potassium perchromate, is an inorganic compound having the chemical formula . It is a red-brown paramagnetic solid. It is the potassium salt of tetraperoxochromate(V), one of the few examples of chromium in the +5 oxidation state and one of the rare examples of a complex stabilized only by peroxide ligands. Heating this compound releases singlet oxygen.
Potassium peroxochromate is prepared starting from chromium trioxide (), excess potassium hydroxide (KOH), and 30% hydrogen peroxide ():
Hydrogen peroxide is added at temperatures below :
The intermediate tetraperoxochromate(VI) is reduced by hydrogen peroxide, forming tetraperoxochromate(V):
Thus, the overall reaction is:
The compound decomposes spontaneously at higher temperatures but may be stored in sealed containers for extended periods.