Using the kinetic molecular theory,explain why air pressure inside a syringe increases if the volume decreases from 15.0 cm

In order to tackle this question a general understanding of the the Kinetic Molecular Theory is required. The theory is based on assumptions of the behaviour of Ideal gases which are: Ideal gases are made up of very small molecules which ideally have no mass and there is no force of attraction between the molecules or between molecules and the walls of the container.The molecules are always in constant random motion and they move in a straight line until they collide with another molecule or the walls of the container.Collisions between the molecules or with the walls of the container are perfectly elastic. This means that a molecule does not lose any kinetic energy during colliosion.

By decreasing the volume, the molecules move from one end of the syringe to the other in a shorter period of time. This means that they hit the walls more frequently causing more force which must lead to an increase in the pressure of the gas. Thus, the pressure of a gas increases as the volume decreases. This is essentially based on Boyle's Law given that the temeparture is constant.