Explain Mond’s process used for refining of nickel.

Explanation

When impurt nickel is heated in a current of CO at 330-350K, it forms, volatile nickel tetracarbonyl leaving behind the impurities. The nickel.tetracarbonyl thus obtained is then hiëated to a higher temperature (450-470 K), when its undergoes thermal.decomposition to give pure nickel.
`underset("Impure nickel")(Ni)+4CO overset(330+350K)to underset("Nickel tetracarbonyl")(Ni(CO)_(4)) +4CO`
`Ni(CO)_(4) overset(450-470K)to underset("Pure nickel")(Ni)+4CO`