Question #44592

Consider the following statements regarding the optical and electronic properties of coordination complexes: \begin{enumerate} \item \ce{[Ni(CO)4]} is intensely colored in the visible region because strong synergic back-bonding lowers the energy of the Metal-to-Ligand Charge Transfer (MLCT) band. \item The absence of visible color in \ce{[Ni(CO)4]} is due to its $d^{10}$ configuration, which precludes $d-d$ transitions, while its MLCT transitions require high-energy UV excitation. \item In \ce{[Cr(CO)6]}, the intense synergic bonding causes the crystal field splitting energy ($\Delta_o$) to be so large that all spin-allowed $d-d$ transitions are shifted into the ultraviolet region, rendering the complex colorless. \item The \ce{C-O} stretching frequency in \ce{[Ni(CO)4]} is higher than that in free \ce{CO} gas due to the donation of electron density from the \ce{CO} $\sigma$-orbital to the metal. \item \ce{[MnO4]-} and \ce{[Ni(CO)4]} possess $d^0$ and $d^{10}$ electronic configurations respectively; hence, both are strictly colorless in the visible region. \item The pink color of \ce{[Co(H2O)6]^{2+}} arises from a Laporte-allowed $d-d$ transition. \item The Effective Atomic Number (EAN) of the central metal in both \ce{[Ni(CO)4]} and \ce{[Cr(CO)6]} is 36. \item Synergic back-bonding in metal carbonyls strengthens the \ce{M-C} bond and weakens the \ce{C-O} bond. \end{enumerate} Let $C$ be the total number of CORRECT statements. Calculate the value of $\Omega$, where $\Omega = (C \times 10) + \text{EAN of Cr in } \ce{[Cr(CO)6]}$.