Which of the following reaction is not involved in corrosion of iron?

Options

A. `Fe(s) to Fe^(2+)(aq)+2e^-`
B. `4OH^(-)(aq) to O_2(g)+2H_2O(l)+4e^-`
C. `4Fe^(2+)(aq)+O_2(g)+4H_2o(l) to 2Fe_2O_3(s)+8H^+(aq)`
D. `2Fe(s)+o_2(g)+4H^+(aq) to 2Fe^(2+)(aq)+2H_2O(l)`

Answer

To determine which reaction is not involved in the corrosion of iron, we need to analyze the processes that occur during iron corrosion, specifically rusting.

### Step-by-step Solution:

1. **Understanding Corrosion**: Corrosion of iron is primarily an electrochemical process where iron reacts with oxygen and moisture (water) to form rust, which is primarily iron(III) oxide (Fe2O3·xH2O).

2. **Identifying the Reactions**:
- **Anodic Reaction**: At the anode, iron (Fe) is oxidized to iron ions (Fe²⁺):
\[ \text{Fe (s)} \rightarrow \text{Fe}^{2+} (aq) + 2e^- \]
- **Cathodic Reaction**: At the cathode, oxygen (O₂) reacts with hydrogen ions (H⁺) to form water (H₂O):
\[ \text{O}_2 (g) + 4\text{H}^+ (aq) + 4e^- \rightarrow 2\text{H}_2\text{O} (l) \]

3. **Overall Reaction**: The overall reaction for the corrosion of iron can be summarized as:
\[ 2\text{Fe (s)} + \text{O}_2 (g) + 4\text{H}^+ (aq) \rightarrow 2\text{Fe}^{2+} (aq) + 2\text{H}_2\text{O} (l) \]

4. **Identifying Non-Corrosion Reaction**: From the provided reactions, we need to identify which one does not participate in the corrosion process. The reaction:
\[ 4\text{OH}^- (aq) \rightarrow \text{O}_2 (g) + 2\text{H}_2\text{O} + 4e^- \]
is not part of the corrosion process of iron. This reaction represents a different electrochemical process and does not contribute to the rusting of iron.

5. **Conclusion**: Based on the analysis, the reaction that is not involved in the corrosion of iron is:
\[ 4\text{OH}^- (aq) \rightarrow \text{O}_2 (g) + 2\text{H}_2\text{O} + 4e^- \]

### Final Answer:
The reaction that is not involved in the corrosion of iron is the one that produces oxygen from hydroxide ions.