We have already learnt in XI STD that gas molecules move randomly without exerting reasonable forces on one another. Unlike gases, in solids the atoms , ions or molecules are held together by strong force of attraction. The general characteristics of solids are as follows,

(i) Solids have definite volume and shape.

(ii) Solids are rigid and incompressible

(iii) Solids have strong cohesive forces.

(iv) Solids have short inter atomic, ionic or molecular distances.

(v) Their constituents ( atoms , ions or molecules) have fixed positions and can only oscillate about their mean positions