Covalent substances - two kinds

Simple molecular covalent substances:-

The atoms in these substances make very strong covalent bonds to form small molecules of two or more atoms.

By contrast, the forces of attraction between these molecules are very weak.

The result of these inter-molecular forces is that the melting and boiling points are very low, because the molecules are easily parted from each other.

Most molecular substances are gases or liquids at room temperature.

Molecular…