Question

what properties of Carbon to form long chain compound.

Answer 1

Carbon has 4 valence electrons, exactly half of the octet.... so it has some metallic properties....so it bonds with other carbon atoms to form long chains (polymers). This phenomenon is called CATENATION

Answer 2

Catenation occurs most readily with carbon, which forms covalent bonds with other carbon atoms to form longer chains and structures. This is the reason for the presence of the vast number of organic compounds in nature.