• Some features of carbon that contribute to the formation of a large number of organic compounds are given below.

• Between two C atoms strong single bonds, double bonds and triple bonds can be formed. It has been observed that compared to Si which is in the fourth group to which C belongs, the C – C, C = C, C≡C and C – H and other bonds that C forms possess higher bond energies

The relevant information is given in the following table.

Bond   Bond energy

C – C      346

C = C     610

C ≡ C     835

C – H     413

Si – Si    226

Si – H    318

• Carbon can form chains containing thousands of atoms and also rings of all sizes.

• A carbon atom can form 4 covalent bonds. Hence, it is seen that a large number of other atoms/groups can get attached to a carbon atom in a chain or ring and that this property contributes to the existence of a large variety of compounds.

• Carbon forms strong covalent bonds not only with other carbon atoms and hydrogen atoms, but also with other non metal atoms such as O, S, P, N, and halogens.