Which of the following does not give oxygen on heating?

Options

A. `KClO_(3)`
B. `Zn(ClO_(3))_(2)`
C. `K_(2)Cr_(2)O_(7)`
D. `(NH_(4))_(2)Cr_(2)O_(7)`

Answer

D

Explanation

Oxygen rich compoudns like chlorate, perchlorate `K_(2)Cr_(2)O_(7)`, etc. when heated give oxygen but ammonium dichromate gives nitrogen gas when heated.
`2KCIO_(3) overset(Delta)to (2KCl) + 3O_(2)uarr`
`2Zn(CIO_(3))overset(Delta)to ZnCl_(2) + 3O_(2)`
`4K_(2)Cr_(2)O_(7) overset(Delta)to (4K_(2)CrO_(4)) + 2Cr_(2)O_(3) + 3O_(2)uarr`
`(NH_(4))_(2)Cr_(2)O_(7) overset(Delta)to N_(2) uarr +Cr_(2)O_(3) + 4H_(2)O`