Question

Which of the following is not the configuration of lanthanide?
(A) $ [Xe]4{f^{10}}6{s^2} $
(B) $ [Xe]4{f^1}5{d^1}6{s^2} $
(C) $ [Xe]4{f^{14}}5{d^{10}}6{s^2} $
(D) $ [Xe]4{f^7}5{d^1}6{s^2} $

Answer 1

Hint :To answer this question, we first need to understand what electronic configuration is. The electron configuration is the distribution of electrons in atomic or molecular orbitals of an atom or molecule. In atomic and quantum chemistry. Each electron is described as travelling independently in an orbital in an average field created by all other orbitals in electronic setups. Configurations are described mathematically by Slater determinants or configuration state functions.

Complete Step By Step Answer:
Lanthanoid - From lanthanum to lutetium, the lanthanide family of chemical elements consists of 15 metallic chemical elements with atomic numbers 57–71. Rare-earth elements are a group of elements that includes these and the chemically comparable elements scandium and yttrium. In general discussions of lanthanide chemistry, the informal chemical symbol Ln is used to refer to any lanthanide. The lanthanides, with the exception of one, are all f-block elements, meaning they fill the 4f electron shell. Although there is some debate about whether lanthanum or lutetium is a d-block element, those who examine the topic generally regard lutetium to be one; it is included because of its chemical similarities with lanthanum.
Here $ [Xe]4{f^{14}}5{d^{10}}6{s^2} $ is the electronic configuration of an element with atomic number 72 i.e., not of the lanthanoid so this is not the configuration of the lanthanoid
So, the final answer is option (C) i.e., $ [Xe]4{f^{14}}5{d^{10}}6{s^2} $ .

Note :
Lanthanides have a wide range of oxidation states. They also show oxidation states of +2, +3, and +4. Lanthanides, on the other hand, have the most stable oxidation state of +3. As a result, elements in other states try to lose or gain electrons in order to reach the +3 state. As a result, those ions become powerful reducing or oxidizing agents.