F.3 chem :monatomic molecule

A molecule cansists of two atoms is called diatomic molecules.
e.g. hydrogen molecule (H2), oxygen molecule (O2)
Monoatomic molecule is a molecule which consists of one atom only. As noble gases exist as single atoms, we can also say the noble gases exist as monoatomic molecules.
e.g. neon, argon

monoatomic molecules are noble gases atoms. since they have fulfilled the octet,they can exist by themselves in one atom. and, this atom is stable, so they are concsidered as molecules.

Carbon monoxide is a diatomic molecule so as CO2 . O2 , H2 , N2 ,.....are monatomic molecules . 2 same atoms can form a molecule .