The property of carbon responsible for the formation of a vast number of compounds is its ability to form strong covalent bonds with other carbon atoms and a variety of other elements. Carbon has four valence electrons, allowing it to form four covalent bonds. This versatility enables carbon to create long chains, branched structures, and rings, leading to an immense diversity of organic compounds. Additionally, carbon’s ability to form stable double and triple bonds further enhances its capacity for complex molecule formation, making it the backbone of organic chemistry.