Answer:
The difference lies in the kind of bond involved.
Step-by-step explanation:
An ionic solid is composed of a network of oppositely charged ions such as sodium chloride solid. An atomic solid is formed by covalent linkage of atoms of the same element to form a three dimensional solid structure such as in diamond and graphite. A molecular solid consists of discreet molecules held together by intermolecular forces. Examples of molecular solids include naphthalene and the fullerenes.