a) Atomicity:
The number of atoms constituting a molecule is known as its ‘atomicity’.
b) Examples :
A molecule of hydrogen consists of two atoms of hydrogen. Here the atomocity is two. Hence it is known as a diatomic molecule. Helium (He), Argon (Ar) exist as single atom. Hence they are known as monoatomic. Ozone (O3) has tetratomic Sulphur (S8) has octatomic
c) Every element has a definite combining capacity, that determines the atomicity of its molecules. Every element reacts with other element according to its combining capacity, which we call as its valency.
