Solids, Liquids and Gases

SOLIDS, LIQUIDS AND GASES

The matter can be classified on the basis of the spacing between the molecules of the matter. Matter exists in two basic principle form such as solid and fluid. Fluid is further subdivided in to liquid and gas.

1. Spacing between molecules

In solids, the molecules are very closely spaced, in liquids the spacing between the different molecules is relatively large and in gases the spacing between the molecules is still larger.

2. Inter molecular bonds

The inter molecular bonds are larger in solids, smaller in liquids and extremely smaller in gases. The solid is very compact and rigid form, liquid molecules can move freely within the liquid and the molecules of gases have greater freedom of movement so that the gases fill the container completely in which they are placed.

3. Deformation due to forces

The deformation due to normal and tangential forces for solids is within the elastics limits such that the deformation disappears and the solid body is restored to its original shape when the stress causing the deformations is removed. When a fluid is subjected to a shearing force it deforms continuously as long as the force is applied. The amount of shear stress in a fluid depends on the magnitude of the rate of deformation of the fluid element. The liquid under ordinary conditions are quiet difficult to compress whereas various gases can be compressed much readily under the action of external pressure.