DIFFERENCES BETWEEN CRYSTALLINE AND AMORPHOUS SUBSTANCES

Differences between crystal and amorphous substances:

All the substances are classified into crystals and amorphous.

1.In crystalline substances the atoms are located in a regular three dimensional arrangement, hence the ions ormolecules have well defined geometrical shape.
Amorphous substances do not have regular arrangement of
particles, therefore do not have well defined shape.

2.crystals have long range order
Amorphous substances have short range order

3.crystals have sharp melting point i.e., they melt at a particular
temperature.
where as amorphous substances do not have sharp melting
point i.e., they melt over a range of temperature.

4.in crystals fusion point is constant
where as amorphous substances do not have constant heat of fusion.

5) crystals are anisotropic, i.e.,their thermal, electrical and optical properties have different values along the three axes
Amorphous substances are isotropic, i.e., they have same values of properties in all directions.

6.crystals are true solids.
where as amorphous materials are are pseudo – solids.

7.examples of crystals: diamond ,metallic substances and common salt etc.
examples of amorphous; rubber, plastic and polymers etc

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