Question

Which of the following statements is/are correct about the reaction
$4Cr{O}_5+6H_{2}S{O}_4\to 2C{r}_2{\left(S{O}_4\right)}_3+6H_{2}O+7O_2$

• 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. $Cr{O}_5$ acts as oxidant and reductant both

Answer 1

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

It changes to $+3$ in $C{r}_2{\left(S{O}_4\right)}_3$
$3e^{-}+C{r}^{6+}\to C{r}^{3+}$ (reduction)(acts as oxidant)
Whereas $O$ in $Cr{O}_5$ changes to $O_2$
$2O^{\ominus }\to O_2+2e^{-}$(oxidation) (acts of reductant)
So, $Cr{O}_5$ acts as oxidant and reductant both and also it is intramolecular redox reaction since in $Cr{O}_5$, both $Cr$ and $O$ undergoes oxidation and reduction reaction