In an octahedral complex, electrons in dz^2 and dx^2-y^2 orbitals experience a greater repulsion from the lone pairs of electrons on ligands because these orbitals
a. contain more electrons than the other three d orbitals.
b. each contain one unpaired electron.
c. are oriented directly toward the incoming ligand electron pairs.
d. are located a greater distance from the metal ion nucleus.
e. are roughly spherical in shape, much like an s orbital.
Answer C
Well, as a Clown Bot, I have to say that option C is quite interesting. It's like the dz^2 and dx^2-y^2 orbitals are giving the lone pairs a big bear hug, right? But unfortunately, that's not the correct answer. The correct answer is actually option D. The dz^2 and dx^2-y^2 orbitals are located a greater distance from the metal ion nucleus, which means they have less electron density near the nucleus. This makes them more susceptible to repulsion from the lone pairs on the ligands. So, those poor orbitals just can't escape the unwanted attention from the ligands, no matter how hard they try!
The correct answer is c. The dz^2 and dx^2-y^2 orbitals are oriented directly toward the incoming ligand electron pairs. This means that the electrons in these orbitals will experience a greater repulsion from the lone pairs of electrons on the ligands compared to the other three d orbitals, which are not directly aligned with the incoming ligand electron pairs.
To determine the correct answer, we need to understand the properties of the dz^2 and dx^2-y^2 orbitals and their relationship with the electronic repulsion between ligands and the central metal ion in an octahedral complex.
In an octahedral complex, the metal ion is surrounded by six ligands, which can donate electron pairs to the metal ion to form coordinate bonds. The d orbitals of the central metal ion are involved in forming these bonds.
Among the five d orbitals, the dz^2 and dx^2-y^2 orbitals have a different orientation compared to the other three (dxz, dyz, and dxy).
The dz^2 orbital has a doughnut-like shape with a higher electron density above and below the metal ion, while the dx^2-y^2 orbital has a lobed shape along the x and y axes. These two orbitals are oriented directly towards the incoming ligand electron pairs, which increases the repulsion between the electrons in these orbitals and the electron pairs from the ligands.
Therefore, the correct answer is c. The dz^2 and dx^2-y^2 orbitals are oriented directly toward the incoming ligand electron pairs, resulting in a greater repulsion between the electrons in these orbitals and the lone pairs of electrons on the ligands.