JEE Advanced · Chemistry · 9. Redox Reactions
Consider the following list of reagents: Acidified , alkaline and . The total number of reagents that can oxidise aqueous iodide to iodine is
- A 2
- B 3
- C 5
- D 7
Answer & Solution
Correct Answer
(D) 7
Step-by-step Solution
Detailed explanation
\(\text{K} _2 \text{Cr} _2 \text{O} _7, \text{CuSO} _4, \text{H} _2 \text{O} _2, \text{Cl} _2, \text{O} _3, \text{FeCl} _3,\) \(\text{HNO} _3\)
\(\text K _2\text{Cr} _2 \text{O} _7+7 \text{H} _2 \text{SO} _4+6 \text{KI} \rightarrow 4 \text{K}_2 \text{SO} _4~+\) \( \text{Cr} _2\left(\text{SO} _4\right)_3+3 \text{I} _2+7 \text{H} _2 \text{O}\)
\(8 \text{HNO} _3+6 \text{KI} \rightarrow 6 \text{KNO} _3+2 \text{NO} +4\text H _2\text O\) \(+~3\text I _2\)
\(2 \text{KMnO} _4+ \text{KI} + \text H _2\text O \rightarrow \text{KIO} _3+2 \text{MnO} _2~+\) \(2 \text{KOH}\)
\(\text K _2\text{Cr} _2 \text{O} _7+7 \text{H} _2 \text{SO} _4+6 \text{KI} \rightarrow 4 \text{K}_2 \text{SO} _4~+\) \( \text{Cr} _2\left(\text{SO} _4\right)_3+3 \text{I} _2+7 \text{H} _2 \text{O}\)
\(8 \text{HNO} _3+6 \text{KI} \rightarrow 6 \text{KNO} _3+2 \text{NO} +4\text H _2\text O\) \(+~3\text I _2\)
\(2 \text{KMnO} _4+ \text{KI} + \text H _2\text O \rightarrow \text{KIO} _3+2 \text{MnO} _2~+\) \(2 \text{KOH}\)
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