Question

What are the three common forms of carbon?

Answer 1

Hint : The three common forms of carbon different in structures and properties. One of them is highly priced and used for making jewelry. One is used in schools for writing. And the last one has a completely different application. They are also called allotropes of carbon.

Complete Step By Step Answer:
The three common forms of carbon are known allotropes of carbon. It can form many allotropes but three forms are most common. These common forms are diamond, graphite, and buckminsterfullerene (buckyball). These three allotropes are of pure carbon.
Diamond: Diamonds are a colorless, transparent, and lustrous form of carbon. Due to their lustrous property, they are used for making jewelry. Carbon atoms in diamonds are arranged into an infinite three-dimensional array in which every carbon atom is linked to four other carbon atoms. Each of these covalent bonds is at an equal angle to each of the other covalent bonds, thus forming a four-sided shape that resembles a pyramid. Because of such bond formation, the diamond is extremely hard and has a high melting point.
Graphite: it contains layers of carbon atoms. Each carbon atom is bonded into its layer with three strong covalent bonds. Graphite is black, shiny, and opaque, and also a very slippery material. It is used in pencil leads because layers easily slide onto the paper, leaving a black mark.
Buckminsterfullerene (buckyball): Fullerenes resemble graphite in that they are composed entirely of carbon atoms that are joined together in sheets of hexagonal rings. But the difference is, some of the carbon rings have five atoms, or more, in them. This forces the sheet of linked rings into the shape of a hollow sphere or tube. Cylindrical fullerenes are also called carbon nanotubes or buckytubes.

Note :
Carbon is capable of forming many more allotropes other than diamond, graphite or buckminsterfullerene, due to its valency. Some unusual forms of carbon exist at very high temperatures or extreme pressures. Graphene is also considered one of the common forms of carbon.