Question

What are noble gases? Why are they also called inert gases?

Answer 1

Hint: The noble gases are present in the periodic table between the most electronegative group (Group 17 – halogen group) and the most electropositive group (Group 1- alkali group). The alkali group loses an electron, to obtain the nearest noble gas configuration, while the halogen group accepts an electron to obtain the nearest noble gas configuration.

Complete Solution :
- The noble gases are the members of the group 18. It is in the far right of the periodic table.
- The noble gases are the only elements whose outer shell is full. Noble gases are highly unreactive due to their stable configuration. Hence, they are also called inert gases.
- There are seven noble gases in the periodic table. They are given in the table below.

Atomic Number	Chemical element	Electronic configuration
2	Helium	2
10	Neon	2,8
18	Argon	2,8,8
36	Krypton	2,8,18,8
54	Xenon	2,8,18,18,8
86	Radon	2,18,32,18,8
118	Oganesson	2,8,18,32,32,18,8

- The noble gases due to their inert configuration do not participate in the chemical bonding.
- They have very less tendency to either lose or gain electrons.
- The reactivity of the noble gases are as follows:
Ne < He < Ar < Kr < Xe < Rn < Og
- Noble gases are odorless, colorless, tasteless and non-inflammable.
- Noble gases such as Kr, Xe and Rn are used as powerful oxidizing agents.
- They can also be used as a reagent for the synthesis of various chemical compounds.

Additional Information:
- Noble gases can absorb or emit electromagnetic radiation.
- They are used in the discharge lamps and fluorescent lightning devices.
- Neon produces orange-red light.
- Xenon emits beautiful blue light.

Note: - Earlier noble gases were labelled as Group 0 in the periodic table because they could not bond or combine with other elements to form chemical compounds.