Question

Which of the following explanation is correct about the given below reaction?
$Cr _2 O _7^{2-}+ H _2 O \rightarrow 2 CrO _4^{2-}+2 H ^{+}$

• A. $Cr$ is reduced
• B. $Cr$ is oxidised
• C. Oxidation number of $Cr$ has neither decreased nor increased
• D. Hydrogen is reduced

Answer 1

Answer: (C)

The oxidation number of $Cr$ in $Cr _2 O _7^{2-}$ and $CrO _4^2-$ is same, i.e. 6. Thus, oxidation of $Cr$ has neither decreased nor increased.