Explain Boyle's law in terms of the kinetic theory?

1 Answer
May 16, 2018

When molecules collide they create pressure. When the molecules are closer together they collide more frequently. Hence less volume more collisions more pressure.


Kinetic theory is based on the kinetic energy of moving particles. The kinetic energy is directly related to the temperature.

In Boyle's Law the temperature is helped constant, so the kinetic energy of the molecules is a constant. The pressure and the volume are inversely related in Boyle's Law.

In Kinetic theory pressure is created by the collision of particles. ( atoms or molecules) with each other and the container. The more collisions the more pressure. An increase in temperature will cause an increase in the number of collisions as the molecules have more kinetic energy. This is not the case in Boyle's Law.

What happens in Boyle's Law is that the molecules are forced more closely together. The more densely packed the gas molecules are the more often they will collide creating more pressure. So if the volume is less the number of collisions and pressure will be greater. If the volume is greater the number of collisions and pressure will be less. So volume and pressure are inversely related if the temperature and total kinetic energy is kept constant.