In chromyl chloride test for confirmation of Cl-, a yellow solution is obtained. Acidification of the solution and addition of amyl alcohol and 10% H2O2 turns organic layer blue indicating formation of chromium pentoxide. The oxidation state of chromium in that is
- \(+6\)
- \(+5\)
- \(+10\)
- \(+3\)
The Correct Option is A
Solution and Explanation
- During the chromyl chloride test, the following reaction occurs:
Cl− + K2Cr2O7 + H2SO4 → CrO2Cl2 + Cl−
- In basic medium, this results in a yellow solution due to CrO42−.
- Upon acidification, addition of amyl alcohol, and 10% H2O2, a blue organic layer forms due to the formation of CrO5 (chromium pentoxide).
- The oxidation state of chromium in CrO5 is +6.
So, the correct answer is: +6
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