Nokea
Balance the following redox reaction in acidic solution: Iâ» (aq) + Crâ‚‚O₇²â» (aq) -> Iâ‚‚ (aq) + Cr³âº (aq). Identify the oxidizing agent and reducing agent.
- A. Iâ» is oxidized, Crâ‚‚O₇²â» is reduced
- B. Iâ» is reduced, Crâ‚‚O₇²â» is oxidized
- C. Both Iâ» and Crâ‚‚O₇²â» are oxidized
- D. Both Iâ» and Crâ‚‚O₇²â» are reduced
Correct Answer: B
Rationale: In the given redox reaction, Iâ» is gaining electrons to form Iâ‚‚, which means Iâ» is being reduced (undergoing reduction). On the other hand, Crâ‚‚O₇²â» is losing electrons to form Cr³âº, indicating that Crâ‚‚O₇²â» is being oxidized (undergoing oxidation). Therefore, Iâ» is the reducing agent and Crâ‚‚O₇²â» is the oxidizing agent. Choice A is incorrect because Iâ» is being reduced, not oxidized. Choice C is incorrect as both species cannot be oxidized in the same reaction. Choice D is incorrect as both species cannot be reduced in the same reaction.
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