Crystalline materials

Amorphous materials

(a)  The constituent's ions or molecules in a given crystalline solid are arranged in a definite geometrical pattern.

The constituent's atoms or molecules in these solids are not arranged in a regular definite geometrical pattern.

(b)  These have a definite external geometrical shape.

These are not regular in their external shape.

(c)  These have a long range order of atoms or molecules.

These do not have a long range order of atoms or molecules.

(d)  All the bonds among molecules in these solids are equally strong. The crystalline solids have a sharp melting point.

Amorphous solid do not have a sharp melting point, because the weakest bond get reputed at lower temperature and stronger bonds get reputed at higher temperature.

(e) These are anisotropic i.e. the bond of crystalline solids have directional properties.

These solids sre isotropic as their physical properties are same in all direction.

In crystalline solids the angles between the flat surfaces of the crystal are constant.

These are super cooled  liquid of high viscosity.