8H++ MnO4- → Mn2+ + 4H2O , which one is correct about given equation?
Correct answer: B. 5e- on L.H.S
- A. 5e- on R.H.S
- B. 5e- on L.H.S
- C. 3e- on R.H.S
- D. 3e- on L.H.S
Explanation
Option B is correct.The balanced equation for the reaction is: MnO4- + 8H+ + 5e- → Mn2+ + 4H2O The oxidation state of manganese changes from +7 in MnO4- to +2 in Mn2+. This means that manganese has lost 5 electrons in the reaction. The number of electrons transferred can be calculated by subtracting the oxidation state of manganese in the reactant from the oxidation state of manganese in the product. In this case, the number of electrons transferred is 7 - 2 = 5. The addition of 5 electrons on the left-hand side of the equation represents the reduction of manganese. Therefore, the answer is 5e- in L.H.S.
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