In which of the following reaction, oxidation number of Cr has been affected?

Options

A. `2CrO_(4)^(2-) + 2H^(+) to Cr_(2)O_(7)^(2-) + H_(2)O`
B. `Cr_(2)O_(7)^(2-) + 2OH^(-) to 2CrO_(4)^(2-) + H_(2)O`
C. `(NH_(4))_(2)Cr_(2)O_(7) to N_(2) + Cr_(2)O_(3) + 4H_(2)O`
D. `CrO_(2)Cl_(2) + 2OH^(-) to CrO_(4)^(2-) + 2HCl`

Answer

C

Explanation

`(NH_(4))_(2) + underset(+6)underset(uarr)(Cr_(2))O_(7) to underset(+3)underset(uarr)(Cr_(2))O_(3)`