Which ion would you expect to have the maximum splitting of - orbitals

Options

A. `[Fe(CN)_(6)]^(-4)`
B. `[Fe(CN)_(6)]^(-3)`
C. `Fe(H_(2)O)_(6)]^(+2)`
D. `[Fe(H_(2)O)_(6)]^(+3)`

Answer

To determine which ion would have the maximum splitting of d-orbitals, we can follow these steps:

### Step 1: Understand d-Orbital Splitting
In an octahedral complex, the five d-orbitals split into two energy levels: the lower-energy t2g orbitals and the higher-energy eg orbitals. The extent of this splitting depends on the nature of the ligands surrounding the metal ion and the number of d-electrons in the metal.

**Hint:** Remember that the splitting of d-orbitals occurs due to the electrostatic interactions between the ligands and the d-electrons of the metal ion.

### Step 2: Identify the Ligands
The strength of the ligand plays a crucial role in the degree of splitting. Strong field ligands (like CN⁻) cause greater splitting compared to weak field ligands (like H2O).

**Hint:** Strong field ligands lead to larger splitting (greater Δo), while weak field ligands lead to smaller splitting.

### Step 3: Analyze the Given Options
We need to analyze the oxidation states and electronic configurations of the metal ions in the given complexes. The options typically include different metal ions and ligands.

**Hint:** Calculate the oxidation state of the metal in each complex to determine how many d-electrons are present.

### Step 4: Calculate the d-Electron Count
For each metal ion, determine the number of d-electrons based on its oxidation state. The more d-electrons present, the lesser the splitting energy, as more electrons lead to increased electron-electron repulsion.

**Hint:** Use the electronic configuration of the metal to find the number of d-electrons after accounting for the oxidation state.

### Step 5: Compare the Splitting
Once you have the d-electron counts for the metal ions in the complexes with strong field ligands, compare them. The complex with the fewer d-electrons will experience greater splitting.

**Hint:** Remember that a lower number of d-electrons in the presence of a strong field ligand leads to maximum splitting of d-orbitals.

### Step 6: Conclusion
After analyzing the options, you will find that the ion with the maximum splitting of d-orbitals is the one with the strong field ligand and the least number of d-electrons.

**Final Answer:** The ion expected to have the maximum splitting of d-orbitals is the one with a strong field ligand and fewer d-electrons, which in this case is option number 2.