Question

a. List two reasons for carbon forming a large number of compounds.

b. Name the type of bonding found in most of the carbon compounds. Why does carbon form compounds mainly by this kind of bonding?

c. Give reason why the carbon compounds- 

1. generally, have low melting and boiling points. 

2. do not conduct electricity in molten state.

Answer 1

The two characteristic properties of the carbon element which leads to the formation of a very large number of organic compounds are: 

1. Catenation
2. Tetravalency

Catenation: Carbon has the unique ability to form bonds with other atoms of carbon, giving rise to large chain molecules. This property is called catenation.
Tetravalency: Carbon has a valency of four. So, it is capable of bonding with four other atoms of carbon or atoms of some other monovalent element.

Carbon compounds form only covalent bonds.Carbon form compounds mainly by covalent bonding because The bonds that carbon forms with most other elements are very strong making these compounds exceptionally stable. One reason for the formation of strong bonds by carbon is its small size. This enables the nucleus to hold on to the shared pairs of electrons strongly. The bonds formed by elements having larger atoms are much weaker.

(i) Carbon compounds generally have low melting points and boiling points because The force of attraction between the molecules of carbon compounds is not very strong. These weak intermolecular forces make them very easy to pull apart from each other. Since they are easy to separate, carbon compounds have low melting and boiling points.

(ii) Carbon compounds do not conduct electricity in the molten state because bonding in carbon compounds does not involve any formation of ions.