Question

Give an example of the gaseous molecule which is a monoatomic.

Answer 1

Monoatomic gas:

• The gases which exist as a single atom in nature are called monoatomic gases.
• They do not form any bonds with other atoms of other elements.
• They are inactive in nature they have stable and complete octets or duplate (commonly outer shells).
• Monoatomic gases contain the same number of electrons and protons and occur mostly in a pure state in nature.

Examples of monoatomic gases:

1. All noble gases like Helium($\mathrm{He}$), Neon($\mathrm{Ne}$), Argon($\mathrm{Ar}$), etc are monoatomic gases.
2. Helium is inactive and monoatomic because of its complete duplate.
3. Neon and Argon are inactive due to their complete octet and hence occur as monoatomic in nature.