Question

Describe a method for refining nickel.

Answer 1

Mond’s process refines nickel. In this process, nickel is heated in the presence of carbon monoxide to form nickel tetracarbonyl, a volatile complex.

\[\ce{Ni + 4 CO ->[330 - 350 K] \underset{Nickel tetracarbonyl}{Ni(CO)4}}\]

Then, the obtained nickel tetracarbonyl is decomposed by subjecting it to a higher temperature (450-470 K) to obtain pure nickel metal.

\[\ce{\underset{tetracarbonyl}{\underset{Nickel}{Ni(CO)4}} ->[450-470 K] \underset{Nickel}{Ni} + 4CO}\]