Which of the following complexes is expected to be diamagnetic?
Practice Questions
Q1
Which of the following complexes is expected to be diamagnetic?
[Fe(H2O)6]3+
[Cu(NH3)4]2+
[Co(NH3)6]3+
[Ni(CO)4]
Questions & Step-by-Step Solutions
Which of the following complexes is expected to be diamagnetic?
Step 1: Understand what diamagnetic means. A substance is diamagnetic if all its electrons are paired, which means it does not have any unpaired electrons.
Step 2: Identify the complex in question, which is [Ni(CO)4].
Step 3: Recognize that CO (carbon monoxide) is a strong field ligand. Strong field ligands cause electrons to pair up in the lower energy orbitals.
Step 4: Determine the electron configuration of nickel (Ni), which is [Ar] 3d8 4s2.
Step 5: When nickel forms the complex [Ni(CO)4], it loses 2 electrons from the 4s orbital and 2 from the 3d orbital, resulting in a 3d10 configuration.
Step 6: Check the electron pairing in the 3d orbitals. Since all 10 electrons in the 3d orbitals are paired, the complex is diamagnetic.
Step 7: Conclude that [Ni(CO)4] is diamagnetic because all electrons are paired due to the influence of the strong field ligand CO.
