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To an acidified dichromate solution,, a ...

To an acidified dichromate solution,, a pinch of `Na_(2)O_(2)` is added and shaken. What is observed?

A

Blue colour

B

Orange colour changing to green

C

Copious evolution of oxygen

D

Bluish-green precipitate

Text Solution

Verified by Experts

The correct Answer is:
A, C
`underset("orange")(Cr_(2)O_(7)^(2-))+10H^(+)+2Na_(2)O_(2) to (##BLJ_VKJ_ORG_CHE_C08_E04_013_S01##) +8Na^(+)+5H_(2)O`
In the absence of ether or amyl alcohol, `CrO_(3)` in acidic medium decomposes to `Cr^(3+)` with evolution of oxygen.
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