10Cr(NO3)3 + 6KMnO4 + 11H2O → 5H2Cr2O7 + 6Mn(NO3)2 + 6KNO3 + 12HNO3
Chromium(III) nitrate react with potassium permanganate and water to produce dichromic acid, nitrate manganese(III), potassium nitrate and nitric acid. This reaction takes place in a diluted nitric acid.