Question

Short note on Uniqueness of carbon

Answer 1

it is the unique in the sense that it has valency 4 and it exist in more than 1 allotropic form

Answer 2

The answer lies with carbon's unique properties. Carbon has an exceptional ability to bind with a wide variety of other elements. Carbon makes four electrons available to form covalent chemical bonds, allowing carbon atoms to form multiple stable bonds with other small atoms, including hydrogen, oxygen, and nitrogen.