Poling is used for the purification of:

Options

A. Oxidise impurities present in stor copper
B. Reduce impurities present in blister copper
C. Reduce impurities using carbon
D. Remove impurities in the form of slag

Answer

**Step-by-Step Solution:**

1. **Understanding Poling**: Poling is a refining process used in metallurgy to purify metals. It involves the use of a pole, typically made of wood, which is inserted into molten metal. The pole helps to reduce metal oxides and remove impurities.

2. **Identifying the Metal**: The primary metal that is purified using the poling process is copper (Cu). During the extraction of copper, the metal may contain oxidized impurities, primarily copper oxide (CuO).

3. **Recognizing the Impurities**: In the case of copper, the impurities are usually in the form of oxides. The poling process helps to reduce these oxides to pure metal. For example, copper oxide (CuO) can be reduced to copper (Cu) during this process.

4. **Application of Poling**: The poling process is typically carried out in a reverberatory furnace, where the molten copper is treated with the wooden pole. The heat from the molten metal causes the wood to burn, producing carbon monoxide, which helps in reducing the copper oxide impurities.

5. **Conclusion**: Based on the understanding of the poling process and its application, we can conclude that poling is primarily used to reduce the impurities present in blister copper.

6. **Final Answer**: Therefore, the correct option is: "Reduce impurities present in blister copper."

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