Write a short note on noble gases.

Explanation

i. Elements present in group 18 on the extreme right of the modern periodic table are called noble gases.
ii. Noble gases include Helium (He), Neon (Ne), Argon (Ar), krypton (Kr), Xenon (Xe), Radon (Rn) and Oganesson (Og).
iii. Their outermost shell contains 8 electrons except helium which contains 2 electrons. Their valency is zero.
iv. These elements are included in p-block of the modern periodic table.