Question

What is the number of unpaired electrons in Lutetium (Lu) in the +3 oxidation state?

• A. 2
• B. 1
• C. 0
• D. 3

Hint:

The number of unpaired electrons can be determined by examining the electron configuration in the oxidation state of the element. If all electrons are paired, the element has no unpaired electrons.

Answer 1

The Correct Option is C

To determine the number of unpaired electrons in Lutetium (Lu) in the +3 oxidation state, we first need to understand its electronic configuration. Lutetium has an atomic number of 71. Therefore, its ground state electron configuration is: [Xe] 4f¹⁴ 5d¹ 6s² 

Lutetium in the +3 oxidation state means it has lost three electrons. These electrons are removed first from the outermost shell following the order of 6s and then 5d: 

• Two electrons are removed from 6s, and one electron is removed from 5d.

Thus, the electron configuration for Lu³⁺ is: [Xe] 4f¹⁴

Next, we look at the 4f sublevel, which is completely filled with 14 electrons. A completely filled sublevel has no unpaired electrons.

Thus, Lutetium in the +3 oxidation state has 0 unpaired electrons.