The Zn acts as sacrificial or cathodic protection to prevent rusting of iron because

Options

A. E_(op) of Zn = E_(op) of Fe`
B. `E_(op) of Zn gt E_(op) of Fe`
C. `E_(op) of Zn lt E_(op) of Fe`
D. Zn dose mot react with water

Answer

To answer the question regarding why zinc (Zn) acts as sacrificial or cathodic protection to prevent rusting of iron, we can break down the explanation into several steps:

### Step-by-Step Solution:

1. **Understanding Rusting**:
- Rusting is an electrochemical process where iron reacts with oxygen and moisture to form iron oxide (rust). This process involves the oxidation of iron.

2. **Role of Zinc**:
- Zinc is more reactive than iron in terms of its position in the electrochemical series. This means that zinc can easily lose electrons compared to iron.

3. **Sacrificial Anode**:
- When zinc is in contact with iron, it acts as a sacrificial anode. This means that zinc will oxidize (lose electrons) preferentially over iron. The reaction can be represented as:
\[ \text{Zn} \rightarrow \text{Zn}^{2+} + 2\text{e}^- \]

4. **Protection of Iron**:
- As zinc oxidizes, it generates electrons that can be used to reduce the iron ions back to metallic iron. This process prevents the iron from losing electrons and thus from oxidizing (rusting).

5. **Electrochemical Cell**:
- In this scenario, zinc acts as the anode of an electrochemical cell, while iron acts as the cathode. The flow of electrons from zinc to iron helps to protect the iron from corrosion.

6. **Conclusion**:
- Therefore, zinc protects iron from rusting by acting as a sacrificial anode, undergoing oxidation itself and thus preventing the oxidation of iron.