Explanation:

The given reaction is:

Fe2 + H2O2 + 2H → Fe3 + 2H2O

To identify the oxidation half-reaction, we need to determine the species that is being oxidized. In this case, Fe2 is being oxidized to Fe3.

To write the oxidation half-reaction, we need to show the loss of electrons. Fe2 is losing one electron to form Fe3. Therefore, the oxidation half-reaction is:

Fe2 → Fe3 + e-

This is represented by option 'A'. However, this is not the correct answer.

Reason:

The correct answer is option 'B', which states that the oxidation half-reaction is:

H2O2 + 2e- → 2OH-

To understand why this is the correct answer, we need to consider the overall reaction and the changes in oxidation states.

In the given reaction, the oxidation state of Fe changes from +2 to +3. This means that Fe is losing one electron and is being oxidized. However, the reaction involves the reduction of H2O2 to OH-.

Explanation of Option B:

Let's break down the reaction step by step:

1. Fe2 + H2O2 + 2H → Fe3 + 2H2O

2. The oxidation state of Fe changes from +2 to +3, indicating that Fe is being oxidized.

3. The oxidation state of H in H2O2 changes from -1 to 0, indicating that H2O2 is being reduced.

4. The oxidation state of O in H2O2 changes from -1 to -2, indicating that O is being reduced.

5. The change in oxidation state of O suggests that it is accepting electrons. Therefore, H2O2 is acting as an oxidizing agent.

6. The product of the reduction of H2O2 is OH-, as it gains two electrons.

7. Therefore, the oxidation half-reaction is: H2O2 + 2e- → 2OH-

This is consistent with option 'B'.

Conclusion:

The oxidation half-reaction for the given reaction is H2O2 + 2e- → 2OH-.