Question

Oxidation number of $Ni$ in $Ni(CO{)}_4$ is:

• A. 2
• B. 3
• C. 1
• D. 0

Answer 1

Answer: (D)

Oxidation state of metal in carbonyl is always zero.
$\therefore$ Oxidation state of $Ni$ in $Ni(CO{)}_4$ is zero.