Question

how to write electronic configuration​

Answer 1

IT'S SO EASY
JUST WRITE
S, S,P,S,P,D,S,P,D,F
THEN NUMBER IT ACCORDING TO THE ORBITS.

Answer 2

An atom's electron configuration is a numeric representation of its electron orbitals. Electron orbitals are differently-shaped regions around an atom's nucleus where electrons are mathematically likely to be located. An electron configuration can quickly and simply tell a reader how many electron orbitals an atom has as well as the number of electrons populating each of its orbitals. Once you understand the basic principles behind electron configuration, you will be able to write your own configurations and tackle those chemistry tests with confidence.