In which of the following changes there is a transfer of the five electrons?
Correct answer: C. MnO41-→ Mn+2
- A. MnO42-→ MnO2
- B. CrO42- → Cr+3
- C. MnO41-→ Mn+2
- D. Cr2O7-2 → 2Cr+2
Explanation
Option C is correct.The only change in the given options that involves a transfer of five electrons is MnO4^- → Mn^2+. In MnO4^-, the oxidation state of manganese is +7. In Mn^2+, the oxidation state of manganese is +2. This means that manganese has lost a total of 5 electrons in the reaction. The balanced equation for the reaction is as follows: MnO4^- + 5e^- → Mn^2+ The balanced equation shows that the number of electrons lost by manganese is equal to the number of electrons gained by the electrons. This is a requirement for a balanced redox reaction.
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