Question

What is atomicity and its kind with examples.

Answer 1

Part 1: Atomicity:

• The number of atoms that constitute the molecule of an element is called its atomicity.

Part 2: Types of Atomicity:

Depending on the atomicity of an element the molecules can be classified as:

(i) Monoatomic molecules: The elements which have only one atom and in which atoms do not join to form a cluster, are called monoatomic molecules. Some examples of monoatomic molecules are hydrogen$\left(\mathrm{H}\right)$, helium $\left(\mathrm{He}\right)$.

(ii) Diatomic molecules: The molecules of elements that have two atoms are called diatomic molecules. Some of the examples are nitrogen$\left({\mathrm{N}}_2\right)$, oxygen $\left({\mathrm{O}}_2\right)$ etc.

(iii) Triatomic molecules: The molecules of elements that have three atoms are called triatomic molecules. An example of triatomic molecules is ozone$\left({\mathrm{O}}_3\right)$.

(iv) Polyatomic molecules: The molecules of elements that have more than three atoms are called polyatomic molecules. Some of the examples of polyatomic molecules are phosphorus $\left({\mathrm{P}}_4\right)$, which has four atoms and is called tetra-atomic.