The most convenient method to protect the bottom of the ship made of iron is

Options

A. coating it with red lead oxide
B. white tin plating
C. connecting it with `Mg` block
D. connecting it with `Pb` block

Explanation

To solve the problem of protecting the bottom of an iron ship from corrosion, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Corrosion**:
- Corrosion is a natural process that leads to the deterioration of metals due to reactions with environmental factors, primarily moisture and oxygen. For iron ships, this can lead to significant damage if not addressed.

2. **Identifying Methods of Protection**:
- There are several methods to protect iron from corrosion, including painting, galvanizing, and using sacrificial anodes.

3. **Evaluating the Sacrificial Anode Method**:
- One of the most effective methods for protecting iron structures, such as the bottom of a ship, is the use of sacrificial anodes. This involves attaching a more electropositive metal, such as magnesium, to the iron structure.

4. **Why Magnesium?**:
- Magnesium is more electropositive than iron, meaning it has a higher tendency to lose electrons. When magnesium is connected to iron, it will corrode preferentially, thus protecting the iron from rusting. This process is known as cathodic protection.

5. **Advantages of Using Magnesium Anodes**:
- Using magnesium anodes is more convenient and cost-effective than painting the entire structure repeatedly. Magnesium can be replaced easily and frequently, ensuring continuous protection against corrosion.

6. **Conclusion**:
- Therefore, the most convenient method to protect the bottom of an iron ship is to attach magnesium blocks as sacrificial anodes. This method is efficient and economical compared to other methods like painting.

### Final Answer:
The most convenient method to protect the bottom of the ship made of iron is to attach magnesium blocks as sacrificial anodes.

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