Question

In the Mond process, nickel reacts with carbon monoxide to form:

• A. NiO
• B. Ni$_2$O
• C. NiCO
• D. Ni(CO)$_4$

Hint:

Mond process uses volatile metal carbonyl for purification of nickel.

Answer 1

The Correct Option is D

Concept: Mond process is used for purification of nickel based on formation of volatile complex: \[ Ni + 4CO \rightarrow Ni(CO)_4 \] This compound is: - volatile - toxic - decomposes at high temperature

Step 1: Formation of carbonyl.
Nickel reacts with carbon monoxide at low temperature: \[ Ni + CO \rightarrow Ni(CO)_4 \]

Step 2: Refining principle.
Ni(CO)$_4$ decomposes at high temperature: \[ Ni(CO)_4 \rightarrow Ni + 4CO \] Thus pure nickel is obtained. Final Answer: \[ \boxed{Ni(CO)_4} \]