Question

Oxidation state of central metal of Ni(Co)4

Answer 1

Ni atom attached with four carbonyl ligands with overall zero charge on the complex has zero oxidation state.Let oxidation state of Ni be X. In a complex sum of oxidation states is always equal to charge on the complex.Also CO is a neutral ligand, means having zero charge.Then sum of oxidations in Ni(CO)4 is as X+4*0=0 OR X=0 Hence oxidation state of Ni is zero