Question

Summarise the rules for writing of distribution of electrons in various shells for the first eighteen elements.

Answer 1

The rules for writing of the distribution of electrons in various shells for the first eighteen elements are given below.

→ If n gives the number of orbit or energy level, then 2\(n ^2\) gives the maximum number of electrons possible in a given orbit or energy level. Thus, First orbit or K-shell will have 2 electrons, Second orbit or L-shell will have 8 electrons, Third orbit or M-shell will have 18 electrons.

→ If it is the outermost orbit, then it should have not more than 8 electrons.

→ There should be step-wise filling of electrons in different orbits, i.e., electrons are not accompanied in a given orbit if the earlier orbits or shells are incompletely filled.