Question

The general electronic configuration of d block elements is $({\text{n}} - 1){{\text{d}}^{1 - 10}}{\text{n}}{{\text{s}}^{1 - 2}}$, where n is the outermost shell. However Palladium does not follow this general electronic configuration. It has an electronic configuration ${\left[ {{\text{Kr}}} \right]^3}^64{{\text{d}}^1}^05{{\text{s}}^0}$ in order to have stability. Give a reason behind it.

Answer 1

In order to make d orbital half filled or fully filed, electron from s subshell jumps to d subshell. As half and fully filled orbitals are more stable.

Complete step by step solution:
In modern periodic tables the elements are organized in such a way that physical and chemical properties of the periodic function of its atomic number. Modern periodic table has 18 groups, 7 periods and 4 blocks. Generally elements of a group have similar outer shell electronic configuration. S block is from group 1 to group 2. Group 1 is known as alkali metal & have ${\text{n}}{{\text{s}}^1}$ electronic configuration. Group 2 is known as alkaline earth metal & has ${\text{n}}{{\text{s}}^2}$ valence electronic configuration. Group 13 to group 18 belongs to the p block & have ${\text{n}}{{\text{s}}^2}{\text{n}}{{\text{p}}^{1 - 6}}$ general electronic configuration. Group 3 to group 12 belong to d block & have $({\text{n}} - 1){{\text{d}}^{1 - 10}}{\text{n}}{{\text{s}}^{1 - 2}}$ .
It is important to note that in d block is that in third period of d block $3{{\text{d}}^4}{\text{ and }}3{{\text{d}}^9}$are not possible, in fourth period of d block $4{{\text{d}}^3},4{{\text{d}}^6}{\text{ and }}4{{\text{d}}^9}$ is not possible and in fifth period of d block $5{{\text{d}}^8}$ is not possible. This is due to the reason of stability. In order to make d orbital half filled or fully filled; electron from s subshell jump to the d sub shell.

Note:
Lanthanides or 4f series are from atomic number 58-71. Actinides or 5f series are from atomic number 90-103. The d block elements are as follow: