A gas consists of particles called molecules which are hard point masses. The molecules are in random motion and obey Newton's laws of motion. Total number of molecules collide with each other and also with the walls of containers. Molecules change their velocities at every collision. The volume of the molecules is a negligibly small fraction of the volume occupied by the gas. No appreciable forces act on the molecules except during a collision. As such molecules follow a straight path between successive collisions called free path. The collisions are elastic and of negligible duration. That is, time spent during collision is very small compared with the time the molecules spend in moving independently.
The kinetic energy of molecules of solid is very less. Solid particles only posses vibrational translatory motion. The distance between The particles of the solid is very less and they cannot be compressed. Because of the above reasons solids have definite shape and volume.
The kinetic energy of molecules of solid is very less. Solid particles only posses vibrational translatory motion. The distance between The particles of the solid is very less and they cannot be compressed. Because of the above reasons solids have definite shape and volume.