Question

The compound in which nickel has the lowest oxidation state is:

• A. $Ni{\left(CO\right)}_4$
• B. ${\left({CH}_{3}COO\right)}_{2}Ni$
• C. $NiO$
• D. $Ni{Cl}_2{\left(P{P}_3\right)}_2$

Answer 1

The correct option is A $Ni{\left(CO\right)}_4$

The oxidation state of nickel in $Ni{\left(CO\right)}_4,{\left({CH}_{3}COO\right)}_{2}Ni,NiO$ and $Ni{Cl}_2{\left(P{P}_3\right)}_2$ are 0, +2,+2 and +2 respectively.
Thus, $Ni{\left(CO\right)}_4$ has lowest oxidation state.