To determine valency.
Step-by-step explanation:
Octet rule is one of the most important rules in the chemistry which says that atom becomes stable when they have eight electrons in their last shell.
All atoms try to have a complete valence shell.This may happen through transfer of electrons or through sharing of electrons.
Octet rule is used most of the times to determine the valency of elements.
If a atom has
electrons in its valence shell,most likely it will have a valency of
.This is because it will get
electrons due to transfer and complete a octet.
Octet rule also explains the non reactivity of the inert gases.
Since they have complete octet,they are already stable.