COMEDK · Chemistry · 9. Redox Reactions
In the reaction,
\(\text{Cr}_2\text{O}_7^{2-} + 4\text{H}_2\text{O}_2 + 2\text{H}^+ \rightarrow 2\text{CrO}_5 + \text{H}_2\text{O}\)
The change in oxidation state of Cr is:
- A No change in oxidation state
- B +6 to +3
- C +3 to +6
- D +6 to +10
Answer & Solution
Correct Answer
(A) No change in oxidation state
Step-by-step Solution
Detailed explanation
In \(\text{Cr}_2\text{O}_7^{2-}\), the oxidation state of Cr is calculated as: \(2x + 7(-2) = -2\) \(2x = +12 \Rightarrow x = +6\) In \(\text{CrO}_5\), the molecule has a butterfly structure containing two peroxo linkages (\(-O-O-\)) and one oxo linkage (\(=O\)). There are four…
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