Question

Which of the following statements is/are correct about the reaction
$4 CrO _5+6 H _2 SO _4 \rightarrow 2 Cr _2\left( SO _4\right)_3+6 H _2 O +7 O _2$

• A. It is disproportionation reaction
• B. It is a an intramolecular redox reaction
• C. Cr acts as oxidant, whereas $O$ acts as a reductant
• D. $CrO _5$ acts as oxidant and reductant both

Answer 1

Answer: (B), (C), (D)

It changes to $+3$ in $Cr _2\left( SO _4\right)_3$
$3 e ^{-}+ Cr ^{6+} \rightarrow Cr ^{3+}$ (reduction)(acts as oxidant)
Whereas $O$ in $CrO _5$ changes to $O _2$
$2 O ^{\ominus} \rightarrow O _2+2 e ^{-}$(oxidation) (acts of reductant)
So, $CrO _5$ acts as oxidant and reductant both and also it is intramolecular redox reaction since in $CrO _5$, both $Cr$ and $O$ undergoes oxidation and reduction reaction