Complete the exercises below. For each of the following metals, write the electronic configuration of the atom and its 3+ ion: b. Mo. Draw the crystal-field energy-level diagram for the d orbitals of an octahedral complex, and show the placement of the d electrons for each 3+ ion, assuming a weak-field complex. How many unpaired electrons are there in each case?

Electronic configuration describes the distribution of electrons in an atom's orbitals. For transition metals like molybdenum (Mo), the configuration is crucial for understanding their chemical properties and behavior in compounds. The configuration for Mo is [Kr] 5s² 4d⁵, and for its 3+ ion, it loses three electrons, typically from the 4d and 5s orbitals.

Crystal Field Theory (CFT) explains how the arrangement of ligands around a central metal ion affects the energy levels of its d orbitals. In an octahedral complex, the d orbitals split into two energy levels: t₂g (lower energy) and e_g (higher energy). This theory helps predict the magnetic properties and color of the complex based on the arrangement and strength of the ligands.

Unpaired electrons in an atom or ion contribute to its magnetic properties. In transition metal complexes, the number of unpaired electrons can be determined by the electron configuration and the splitting of d orbitals. A weak-field ligand leads to a higher number of unpaired electrons, resulting in paramagnetism, while a strong-field ligand can lead to paired electrons and diamagnetism.