1. The problem asks why there is an exceptionally large number of carbon compounds. 2. The key reason lies in the unique properties of carbon atoms, especially their ability to form strong covalent bonds with other atoms, including themselves. 3. Carbon has four valence electrons, allowing it to form up to four covalent bonds with other atoms. 4. This tetravalency enables carbon to form a variety of structures such as chains, branched chains, and rings. 5. Carbon-carbon bonds can be single, double, or triple bonds, increasing the diversity of possible compounds. 6. Additionally, carbon compounds can include various functional groups, further expanding the number of possible compounds. 7. This versatility in bonding and structure leads to an exceptionally large number of carbon compounds, which is fundamental to organic chemistry and life. Final answer: The exceptionally large number of carbon compounds is due to carbon's tetravalency and ability to form strong covalent bonds with many elements, including itself, resulting in diverse and complex structures.