Question

Write electronic configuration of sodium.

Answer 1

Hint:Every atom has a nucleus and electrons. In an atom, the arrangement of electrons is known as electronic configuration. In an atom electrons are arranged in energy levels around the nucleus.

Complete step-by-step answer:Electronic configuration also known as electronic structure is the arrangement of electrons in energy level around the atomic nucleus.In atoms there are many shells present, shells are divided into subshells and subshells are further divided in orbitals electrons of the atom are present in orbitals.In a shell maximum four types of Orbital can be present these are s, p, d, f orbitals where electron can be present.Electrons in atom are arranged according to Aufbau principle,Aufbau principle : According to the Aufbau rule "In the ground state of an atom electrons can be filled in atomic orbitals of the lowest available energy level before occupying higher energy levels"Example : The 1s subshell will be filled before the 2s subshell.Order of filling of subshells,
1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s, 4d, 5p, 6s,
Electronic configuration of Sodium :First of all, we will know there are how many electrons are present in an atom of sodium,Atomic number of sodium = 11.So, in the ground state there are 11 electrons present in an atom of sodium.There can be maximum two electrons in s subshell and 6 in p subshell.So, according to the aufbau rule, 1s subshell will be filled first than 2s subshell then 2p subshell then 3p subshell will be filled.Show electronic configuration of sodium is
${}_{11}Na\Rightarrow 1s^2,2s^2,2p^6,3s^1$

Note:Every element has a unique electronic configuration. Electronic configuration determines the chemical reactivity and stability of the element. Electronic configuration tells about the structure of an atom of elements.