What happen when a solution of potassium chromate is treated with an excess of dil. Nitic acid?

Options

A. `Cr_(2)O_(7)^(2-)` and `H_(2)O` are formed
B. `CrO_(4)^(2-)` is reduced to `+3` state of Cr
C. `CrO_(4)^(2-)` is oxidized to `+7` state of Cr
D. `Cr^(3+)` and `Cr_(2)O_(7)^(2-)` are formed

Answer

A

Explanation

(a) When a solution of potassium chromate is treated with an excess of dilute nitric acid. Potassium dichromate and `H_(2)O` are formed.
`2K_(2)CrO_(4)+2HNO_(3)rarrK_(2)Cr_(2)O_(7)+2KNO_(3)+H_(2)O`
Hence `Cr_(2)O_(7)^(-) ` and `H_(2)O` are formed