Question

Nickel is purified by thermal decomposition of its __________

• A. Hydride
• B. Azide
• C. Chloride
• D. Carbonyl

Answer 1

The correct option is D

Carbonyl

The correct answer is (D):-

Explanation for the correct answer:

Mond's Process:-

1. Metal that is particularly refined by using this Mond's Process or the Carbonyl Process is Nickel.
2. This process is basically used for the extraction or the purification of the Nickel metal.
3. Nickel oxides are actually converted into the pure Nickel , and during this process Nickel is heated in the Carbon monoxide gas.
4. Reaction :- $\underset{\mathrm{Nickel}}{\mathrm{Ni}}+\underset{\mathrm{Carbon}\mathrm{monoxide}}{4\mathrm{CO}}\stackrel{300-350\mathrm{K}}{\to }\underset{\mathrm{Nickel}\mathrm{carbonyl}}{\mathrm{Ni}{\left(\mathrm{CO}\right)}_4}$
5. This reaction will further lead to the formation of the volatile Nickel Carbonyl.
6. Reaction :- $\underset{\mathrm{Nickel}\mathrm{carbonyl}}{\mathrm{Ni}{\left(\mathrm{CO}\right)}_4}\stackrel{493-523K}{\to }\underset{\mathrm{Nickel}}{\mathrm{Ni}}+\underset{\mathrm{Carbon}\mathrm{monoxide}}{4\mathrm{CO}}$

Therefore, the correct answer is (D):- Carbonyl