Question

Which of the following characteristics of carbon is responsible for the variety of carbon-based molecules on Earth?

A) It can form bonds.

B) It can form proteins.

C) It has four valence electrons.

D) It is organic in nature.

Answer 1

Carbon needs four valence electrons to complete its outer electron shell, which means it can form bonds with four other molecules. This is responsible for all its wonderful properties.

Actually, the next lightest element which can form four bonds is silicon - but if life were based on silicon we'd all breath sand. I always found that interesting, anyway.