Coating of zinc on iron objects is commonly known as _____.

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the term used to describe the process of coating zinc on iron objects.

2. **Identifying the Process**: The process of applying a protective layer of zinc onto iron is a well-known method in metallurgy.

3. **Defining the Term**: The term used for the coating of zinc on iron objects is "galvanization."

4. **Purpose of Galvanization**: The primary purpose of galvanization is to protect iron from corrosion. The zinc layer acts as a barrier, preventing moisture and oxygen from reaching the iron surface.

5. **Conclusion**: Therefore, the coating of zinc on iron objects is commonly known as galvanization.

**Final Answer**: Galvanization

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