What is atomicity? Name one diatomic molecule.

Hint: Atomicity is the total numbers of atoms that constitute a molecule. So if an element is considered it is composed of one atom. So, it is called monatomic. If there are two atoms then it is called a diatomic molecule. If there are atoms then a triatomic molecule is formed and so on.

Complete answer:
Atomicity is a term widely used in chemistry. In simple terms, atomicity is the total number of atoms present in one molecular of and elements, compound or a substance.
There is a simple way to calculate the atomicity of any element. It can be determined as a ratio of molecular mass and atomic mass. For example, let us take the case of oxygen molecules. The molecular mass of oxygen is \[32{\text{ }}\left( { = 2 \times 16} \right)\] while the atomic mass is 16. If we divide the molecular mass of oxygen by the atomic mass, we get the atomicity as two.
Now atomicity can be monatomic (1), diatomic (2), triatomic (3), tetratomic (4) and so on. One example of each would be:
Monatomic molecular: Helium (\[He\] )
Diatomic Molecular: oxygen (\[{O_2}\] )
Triatomic Molecular: ozone (\[{O_3}\] )
Tetratomic Molecular: Phosphorus (\[{P_4}\] )
Diatomic molecules are those, which have two atoms forming the molecule. Examples of diatomic molecules can be many. Some of them are:
Oxygen molecule (\[{O_2}\]), Hydrogen molecule (\[{H_2}\]), Carbon monoxide (\[CO\] ), Nitric oxide or nitrogen monoxide (\[NO\] ), Bromine liquid (\[B{r_2}\] ), etc.

Note: The students look up the atomicity of different molecules cab. The example of diatomic molecules is vast. Atoms combine to form molecules in order to gain stability. This can be obtained by the combination of two, three or more numbers of atoms. Students can try to calculate the atomicity of different elements by the formula given above.