Question

The most abundant noble gas in the atmosphere is :
A. Argon
B. Neon
C. Helium
D. Krypton

Answer 1

Firstly it is important to know that the noble gases are the almost unreactive gases found in the last group of the periodic table. There are practically $7$ of them known, out of them many are very rarely found in the atmosphere. Then we can write the probable percentage of their existence and can observe the one with the most percentage.

Complete step by step answer: Noble gases belong to the last group of the periodic table as they are almost unreactive in most of the situations apart from some extensive cases. This is primarily the reason they are named as the noble gases.
Now, as we know there are mainly 7 noble gases known into existence, with helium the first and then neon , argon, krypton, xenon, and the radioactive radon. Out of all these gases xenon is perhaps the most reactive and shows a lot of reaction especially with the halogens, ( the group $17$ ).
Though their inactivity makes them very stable, at the same time it makes them rare in the open environment too. That’s why they comprise less than $1\%$ of the space in the atmosphere nearly, non-existent. Predominantly found Noble gases in the environment are :
Argon with the most percentage. Nearly $0.934\%$ of the atmosphere
Neon with the next in line. Nearly $0.00189\%$ of the atmosphere
Helium with the next in line. Nearly $0.00052\%$ of the atmosphere
Apart from that others are practically nonexistent in the atmosphere.
Therefore the answer would be option A, Argon.
So, the correct answer is “Option A”.

Note: There was another noble gases said to be found. Its name was given to Oganesson. Oganesson (Og) is variously predicted to be a noble gas as well or to break the trend due to relativistic effects; its chemistry has not yet been investigated.