(N/A) The kinetic molecular theory provides a microscopic model for the behavior of gases based on the following postulates:
$1$. $Gases$ consist of a large number of identical particles (atoms or molecules) that are so small and so far apart that the actual volume of the molecules is negligible compared to the empty space between them. They are considered as 'point masses',which explains the high compressibility of gases.
$2$. There is no force of attraction between the particles of a gas at ordinary temperature and pressure. This explains why gases expand to occupy all available space.
$3$. Particles of a gas are in constant,random motion in straight lines. If they were at rest,the gas would have a fixed shape,which is not observed.
$4$. Gas pressure is exerted due to the collision of particles with the walls of the container.
$5$. Collisions of gas molecules are perfectly elastic. This means the total kinetic energy of the molecules remains constant before and after the collision,even if individual energies change.
$6$. At any given temperature,although individual particles have different speeds and kinetic energies that change constantly due to collisions,the overall distribution of speeds remains constant.