Question

What is the atomicity of ${F_2}$ ?

Answer 1

We know that atoms combine to form molecules. Atomicity can be defined as the number of atoms present in a single molecule of an element, compound. We can also define atomicity as the total number of atoms that composes a molecule.

Complete answer:
We have seen that atomicity is the total number of atoms that constitute a molecule. The compounds can be classified into;
Monoatomic: The molecules of many elements are composed of only a single atom of that element. For example: Helium $\left( {He} \right)$ , it’ll have atomicity one.
Diatomic: The diatomic molecules are composed of two atoms. For example: ${O_2}$ molecule. It will have atomicity two
Triatomic: The triatomic molecules are composed of three atoms as a result their atomicity will be three. For example: $C{O_2}$
Tetratomic: The tetratomic molecules are composed of four atoms, having atomicity four. For example: $S{O_3}$
Coming to our question;
It should be clear by now that ${F_2}$ is a diatomic molecule. Thus, the atomicity of ${F_2}$ is two.

Note:
Atomicity can be easily determined by calculating the number of atoms present per molecule of a substance. It has no relation with the number of electrons in the atom. It has been found that atomicity may vary in different allotropes of the same element.