Question

Why do covalent compounds have low melting and boiling points ?

Answer 1

In covalent compounds, the atoms are linked by covalent bonds formed by electron sharing. Since no ions are present in these, the attractive forces are quite weak.

The covalent bond is the kind of bond formed by the equal sharing of electrons. The shared electrons are called ‘bonding pairs of electrons. Covalent bonds are very stable and the interatomic forces are quite strong. But, the intermolecular forces between covalent compounds are weak. Covalent compounds are held together by weak intermolecular forces. It is because of such weaker forces, which fail to make the compound bind tightly.

Since the forces are weak, it needs only a little amount of energy to break. Heat is a form of energy. Since lower heat (energy) is capable of breaking these weak intermolecular forces.

As a result, the covalent compounds have low melting and boiling points.