Acidified solution of chromic acid on treatment with H2O2 gi... | CHEMISTRY - REDOX REACTIONS AND ELECTRODE PROCESSES | SolveeIt | Solveeit

Today, August 23

Question

Acidified solution of chromic acid on treatment with H₂O₂ gives blue colour which is due to –

A

CrO₃ + H₂O + O₂

B

Cr₂O₃ + H₂O + O₂

C

CrO₅ + H₂O

D

H₂Cr₂O₇ + H₂O + O₂

Answer

CrO₅ + H₂O

Explanation

Solution

K₂Cr₂O₇ + H₂SO₄ + 4H₂O₂ ® 2CrO₅ + K₂SO₄ + 5H₂O

Chromic peroxide

The blue colour due to chromic peroxide fades away gradually due to decomposition of CrO₅ to Cr³⁺ ions and oxygen.