Describe the preparation of potassium dichromate from chromite ore. What is the effect of increasing pH on solution of potassium dichromate ?

Explanation

Preparation from chromite: For answer, consult Section 8.
Effect to increasing pH: The solution of potassium dichromate `(K_(2)Cr_(2)O_(7))`in water is orange in colour. Increasing the pH i.e. on adding the base, the potassium dichromate changes to potassium chromate `(K_(2)Cr_(2)O_(4))` which yellow in colour. Thus, on increasing the pH, the colour of the solution changes from orange to yellow.
`underset("(Orange)")(K_(2)Cr_(2)O_(7)(aq))+2KOH(aq) to underset("(Yellow)")(2K_(2)CrO_(4)(aq))+H_(2)O(l)`