Spherical or cage-like molecules, such as Buckminsterfullerene ( C60cap C sub 60 Summary Table: Key Concepts Definition Covalent Bond Chemical bond formed by sharing electrons. Valency The combining capacity of an atom (4 for Carbon). Catenation Property of forming long chains or rings. Allotropy Existence of an element in more than one physical form. Class 10 Notes: Carbon Compounds | PDF - Scribd

Having a valency of four allows carbon to bond with four other atoms (of carbon or other elements like H, O, N, and halogens).

(Anion): It is extremely difficult for a small nucleus with only 6 protons to hold onto 10 electrons (6 original + 4 gained). Cannot form C4+cap C raised to the 4 plus power

Carbon compounds exhibit distinct physical properties that differentiate them from ionic compounds:

A hard, three-dimensional tetrahedral structure where every carbon is bonded to four others; it is a non-conductor.

A soft, layered hexagonal structure where each carbon is bonded to three others; it is an excellent conductor of electricity.

Carbon is a non-metallic element that serves as the "king of all elements" because it forms the basis of all known life and millions of synthetic materials. 6. Atomic Mass: 12 U.

The immense number of carbon compounds (over 3 million) is due to two unique properties: