Vapour phase refining can be carried out in case of

Options

A. Ni
B. Zr
C. Ti
D. All of these

Answer

### Step-by-Step Solution:

1. **Understanding Vapor Phase Refining**:
- Vapor phase refining is a method used to purify metals based on their volatility. It involves converting a metal into its vapor form and then condensing it back to solid form, leaving impurities behind.

2. **Identifying Suitable Metals**:
- For vapor phase refining to be effective, the metal in question must possess a certain degree of volatility. This means that the metal should be able to easily transition from a solid to a gaseous state.

3. **Examples of Metals**:
- Common metals that can undergo vapor phase refining include Titanium (Ti) and Zirconium (Zr). These metals are known for their volatile nature, making them suitable candidates for this refining process.

4. **Conclusion**:
- Based on the properties of the metals and their ability to be converted into vapor, we can conclude that vapor phase refining can be carried out for metals like Titanium and Zirconium.

### Final Answer:
Vapor phase refining can be carried out in the case of metals such as Titanium and Zirconium.

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