What is the Difference Between Amorphous and Crystalline Solid?

The main difference between amorphous and crystalline solids lies in the arrangement of their constituent atoms. Here are the key differences between the two:

  1. Arrangement of atoms: Crystalline solids have a regular and ordered arrangement of atoms, while amorphous solids have an irregular and disordered arrangement of atoms.
  2. Anisotropy/Isotropy: Crystalline solids are anisotropic, meaning their properties are different in different directions, while amorphous solids are isotropic, meaning their properties are the same in all directions.
  3. Melting point: Crystalline solids have sharp melting points, while amorphous solids do not have a specific melting point and instead soften gradually over a temperature range.
  4. Shape: Crystalline solids have well-defined edges and faces, while amorphous solids have irregular or curved surfaces.
  5. X-ray diffraction: Crystalline solids diffract x-rays, producing well-resolved diffraction patterns, while amorphous solids do not give well-resolved x-ray diffraction patterns.

Examples of crystalline solids include diamonds and potassium nitrate, while examples of amorphous solids include glass, cellophane, and polyvinyl chloride.

Comparative Table: Amorphous vs Crystalline Solid

The main difference between amorphous and crystalline solids lies in the arrangement of their atoms or molecules. Here is a comparison table highlighting the key differences between the two types of solids:

Property Crystalline Solids Amorphous Solids
Atomic Arrangement Regular 3D arrangement Irregular arrangement
Melting Point Sharp melting point No specific melting point
Anisotropy/Isotropy Anisotropic Isotropic
Symmetry Symmetrical Unsymmetrical
Rigidity More rigid Less rigid
Long/Short-range Order Long-range order Short-range order
Examples Potassium nitrate, copper Cellophane, polyvinyl chloride

Crystalline solids have a regular, repeating three-dimensional array of atoms or molecules, which results in sharp melting points and well-defined edges and faces. In contrast, amorphous solids have an irregular arrangement of atoms or molecules, no specific melting point, and are isotropic in nature.