Consider the following statements regarding metal carbonyls: A. [Ni(CO)₄] exhibits a square planar geometry. B. The metal-carbon bond in metal carbonyls possesses both and character. C. The oxidation state of the central metal atom in [Fe(CO)₅] is zero. D. Synergic bonding involves electron donation from filled metal d -orbitals into empty antibonding ^ * orbitals of CO. Choose the correct answer from the options giv

Step-by-step solution

Statement A is incorrect. In [Ni(CO)₄] , the oxidation state of nickel is zero. The electronic configuration of Ni is [Ar] 3d^8 4s^2 . In the presence of the strong field ligand CO, the 4s electrons are forced to pair up in the 3d orbitals, resulting in a 3d¹⁰ configuration. The hybridization is sp^3 , which corresponds to a tetrahedral geometry, not square planar. Statement B is correct. The metal-carbon bond in metal carbonyls possesses both and character. The bond is formed by the donation of a lone pair of elec