Question

Give a reason for chemical inertness of noble gases.

Answer 1

Hint: The modern periodic table includes elements distributed in 18 groups and 7 periods. Each group is given different names based on the properties and names of the elements in the particular group. For example, group 1 elements are called Alkali metals, Group 2 are called Alkaline earth metals, Group 17 are called halogen families. Similarly, Group 18 elements are called noble gases.

Complete step by step answer:
The Group 18 elements (Noble gases) are Helium, Neon, Argon, Krypton, Xenon, and Radon. We know their atomic numbers are 2, 10, 18, 36, 54, and 63 respectively.
We know that if an element has a fully filled orbital or half-filled orbital, it is said to be more stable. An element is said to be more stable when it is in its completely filled state- or it exhibits an octet electronic configuration. To complete the octet, elements react with each other forming compounds. All the elements try to achieve this stable state.
Let us now look at the electronic configuration of the noble gas. It is $n{s^2}n{p^6}$. We can see that it has a completely filled outermost orbital.
An inert substance or an element is one that does not normally react and form compounds. It can also be called inactive.
As we already discussed the noble gases have an octet electronic configuration in their outermost orbital. So it does not tend to accept, lose, or share electrons between other elements. Thus, it does not form compounds under normal conditions. So we can say that noble gases are inert or chemically unreactive.

Note: Noble gases are also called inert gases because of this reason. The inert property of noble gases can also be explained due to its high ionization enthalpy and positive electron gain enthalpy.
While it was earlier believed to be inert, noble gases also form compounds under specific conditions. In 1962, $Xe{F_2}$ was obtained. It forms halides, oxides, and oxyhalides.