1. Consider the two complexes [Mn(H 2O)6]2+ versus [Mn(CN)6]4-. Diagram the expected orbital splitting diagram for each complex, predict the number of unpaired electrons (if any), and identify the ion as low or high spin.
2. Predict the electron configuration of an octahedral d4 complex with (a) strong field ligands and (b) weak field ligands, and state the number of unpaired electrons in each case.
3. Predict which of the following complexes absorbs light of the shorter wavelength and explain your reasoning: [Co(H2O)6]3+ or [Co(en)3]3+.