Assertion : Nickel can be purified by Mond process.
Reason : `Ni(CO)_(4)` is a volatile compound which deomposed at `460K` to give pure `Ni`.

Options

A. Both assertion and reason are true and reason is the correct explanation of assertion.
B. Both assertion and reason are true but reason is not the correct explanation of assertion.
C. Assertion is true but reason is false
D. Assertion is false but reason is true.

Explanation

**Step-by-Step Solution:**

1. **Understanding the Assertion**: The assertion states that nickel can be purified by the Mond process. The Mond process is a method used for the purification of nickel, which involves the formation of a volatile nickel carbonyl compound.

2. **Understanding the Reason**: The reason provided is that Ni(CO)₄ (nickel tetracarbonyl) is a volatile compound that decomposes at 460 K to give pure nickel. This is a crucial detail because it explains how the purification occurs.

3. **Explaining the Mond Process**:
- In the Mond process, nickel is reacted with carbon monoxide (CO) at temperatures between 330 K to 450 K to form nickel tetracarbonyl (Ni(CO)₄).
- The reaction can be represented as:
\[ \text{Ni} + 4 \text{CO} \rightarrow \text{Ni(CO)}_4 \]
- This compound is volatile, which allows it to be separated from impurities.

4. **Decomposition of Ni(CO)₄**:
- The volatile nickel carbonyl (Ni(CO)₄) is then heated to a higher temperature (around 460 K) where it decomposes back into nickel and carbon monoxide:
\[ \text{Ni(CO)}_4 \rightarrow \text{Ni} + 4 \text{CO} \]
- This step yields pure nickel.

5. **Conclusion**: Both the assertion and the reason are true. The reason correctly explains the assertion because the volatility of Ni(CO)₄ and its decomposition at 460 K are essential for the purification of nickel in the Mond process.

**Final Answer**: Both assertion and reason are true, and the reason is the correct explanation of the assertion.

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