Question

Describe the preparation of K2Cr2O7 from Chromite ore.What happens when K2Cr2O7 is heated strongly?

Answer 1

Potassium dichromate is usually prepared by the reaction of potassium chloride on sodium dichromate. Alternatively, it can be also obtained from potassium chromate by roasting chromite ore with potassium hydroxide. It is soluble in water and in the dissolution process it ionizes: K2Cr2O7 → 2 K+ + Cr2O.