Hint: Noble gases are colourless , odourless and monatomic gases. They are present in the air. Some of these gases are also used in lamps and headlights of cars. They usually do not react.
Complete Solution :
- Noble gas is any of the seven chemical elements that forms the part Group 18 (VIIIa) of the periodic table. The noble gases are helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), radon (Rn), and oganesson (Og).
- The noble gases are the chemical elements present in group 18 of the periodic table. They are the most stable as they have the maximum number of valence electrons present in their valence shell . Therefore, they rarely react with other elements as they already have stable Electronic configuration.
The noble gases, in ascending order of their density, are helium, neon, argon, krypton, xenon and radon. - They are called noble gases because they are so majestic that, in general, they don't react with any other compounds. For this reason they are known as inert gases as they are inert in nature.
Krypton is the rarest noble gas.
- Noble gases consist of other characteristics like they conduct electricity, fluoresce, they are colourless and odourless, and they are used in many conditions when a stable element is needed to maintain a safe and secure environment.
- When exposed to the atmosphere, the noble gases get dissolved in seawater. For each noble gas, these solubility concentrations become a function of temperature, salinity, and pressure.
So as the noble gas is present in the atmosphere so it is also known as aerogenes.
So, the correct answer is “Option C”.
Note: All the noble gases except radon occur within the atmosphere. They're chemically unreactive. They need their valence shell orbitals completely filled. Since nonmetals are the element which accepts electrons to complete their octet while noble gases have already got a whole octet.