Which of the following elements is responsible for oxidation of water to `O_(2)` in biological processes ?

Options

A. Fe
B. Cu
C. Mn
D. Mo

Explanation

To determine which element is responsible for the oxidation of water to oxygen (O₂) in biological processes, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Process**:
- In biological processes, water (H₂O) is oxidized to oxygen (O₂).
- The oxidation state of oxygen in water is -2, while in molecular oxygen, it is 0.

2. **Identifying the Element**:
- We need to identify which transition metal is involved in this oxidation process.
- The element that plays a critical role in this reaction is manganese (Mn).

3. **Electronic Configuration of Manganese**:
- The electronic configuration of manganese is [Ar] 4s² 3d⁵.
- This configuration indicates that manganese has five unpaired electrons in its 3d subshell.

4. **Role of Manganese in Photosynthesis**:
- In photosynthesis, specifically in photosystem II, manganese acts as a cofactor.
- It is part of the oxygen-evolving complex that facilitates the oxidation of water to produce oxygen.

5. **Conclusion**:
- Therefore, the element responsible for the oxidation of water to O₂ in biological processes is manganese (Mn).

### Final Answer:
Manganese (Mn) is responsible for the oxidation of water to O₂ in biological processes.

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