Liquation process may be applied for the purification of.

Options

A. Copper
B. Tin
C. Iron
D. Lead

Answer

### Step-by-Step Solution:

1. **Understanding Liquation Process**:
- The liquation process is a method used for the purification of metals. It is particularly useful for metals that have a low melting point and are mixed with impurities that have a higher melting point.

2. **Identifying Suitable Metals**:
- To determine which metals can be purified using liquation, we need to identify which metals have a low melting point. Common metals that are known to have low melting points include tin and lead.

3. **Process Description**:
- In the liquation process, the impure metal is heated on a sloping hearth of a furnace. As the metal heats up, the pure metal melts and flows down the slope, while the impurities, which have a higher melting point, remain behind on the hearth.

4. **Conclusion**:
- Based on the characteristics of the metals, the liquation process can be applied for the purification of tin and lead. Therefore, the correct options are tin (option B) and lead (option D).

### Final Answer:
The liquation process may be applied for the purification of tin and lead.

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