Classification of solids

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                            Solids:-

   Solids : The solids are the forms of matter in which atoms ands molecules are strongly bound and maintain definite volume and sharp unless changes by applying external forces.

Solid state physics:- The solid state physics is the study of the physical properties of the atomic/molecular matter in the solids state. These physical properties include crystal structure, bonding,thermal, electric and magnetic properties.

Classification of solids:

        Solids are classified into two categories;

(1) crystalline solids

(2) Amorphous solids.


(1) crystalline solid:-

       The crystalline solids are defined as an ordered periodic arrangements of atoms, molecules or ions .

Properties of crystalline solids:-

• The internal arrangements of atoms,ions or molecules of crystalline solids is in a definite order.

• The crystalline solids have a sharp melting point.

• Below the temperature of crystallization, the crystalline material are in a stable state. As the stable state is the state of minimum energy, material acquired a state of minimum energy on crystallization.

• The orderly arrangements of atoms ,ions or molecules in crystal is extended over a large volume of the crystal, indicating a long range order by the atoms, ions or molecules.

• The crystalline solids are anisotropic. This implies that physical properties such as refractive index conducting, thermal properties such as expansion ets. are different in different directions, this is due to orderly arrangements of the constituent.

• Crystalline solids have uniform chemical composition throughout .

Examples:- Diamond, fe, Ag, Au, salt, suger etc.


(2) Amorphous solids:-

       Solids in which constitutes are arranged in irregular or random manner are called amorphous solids.

Properties of amorphous solids:-

• The constituent are arranged in irregular manner.

• They do not have sharp melting point because the bonds between the atoms are not equally strong.

• They are isotropic in nature.

• Amorphous solids are regards as supercooled or pseudo solids.


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