Atomicity not explained in atomic structure chapter by Byju. So concept uncleared
Atomicity is the total number of atomspresent in one molecule of an element, compound or a substance. For example, in O2, there are 2 atoms of oxygen.[citation needed]
Atomicity -
Monatomic -consist of 1 atom
Diatomic -consist of 2 atom
Triatomic -consist of 3 atoms
Polyatomic-consist of 4 or more atoms .