The purification of crude metals is referred to ______.

Answer

**Step-by-Step Text Solution:**

1. **Understanding the Question**: The question asks for the term used to describe the process of purifying crude metals.

2. **Identifying the Process**: The purification of crude metals involves various techniques to remove impurities and obtain the pure form of the metal.

3. **Defining the Term**: The specific term used for the purification of crude metals is "refining."

4. **Explanation of Refining**: Refining is a process that separates the desired metal from its impurities. It can involve various methods, including distillation, electrolysis, and chemical treatments, depending on the type of metal and its impurities.

5. **Conclusion**: Therefore, the purification of crude metals is referred to as "refining."

**Final Answer**: The purification of crude metals is referred to as refining.

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